Shooters Forum banner

Handloads not getting anywhere near manula velocities

5K views 47 replies 32 participants last post by  unclenick 
#1 · (Edited)
Handloads not getting anywhere near manual velocities

Hi guys, I hope this is right place for this.

Lately none of my hand loads have been anywhere near the published velocities for that particular load. For example, for my 30-06 I worked up a load from the Nosler 9th edition manual using their 150 grain E-tip. I used 57.5 grains of IMR 4350 with a case over ll length of 3.300", using CCI Br2 primers, case trimmed to lengh 2.484". I'm shooting it out of a Thompson Center Icon Classic, 24" barrel with the 5r rifling. I put each shell through a Lee factory crimp as well and my tolerances are within 0.0005 of the c.o.a.l. using a digital caliper. It should be around 2880/2900 fps but as you can kind of see in the picture, I barely got 2775. I was using a F1 Master Chronograph 10' away from the barrel. It was 57 out, sunny, no wind and with 72% humidity at an altitude of 2,200 feet above sea level. What am I doing wrong? Should Io seat them lower? I mean the grouping at 100m is stellar but at this velocity its basically a long .308 win. Thanks for your input.

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18122313.jpg

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18074029.jpg
 
See less See more
#2 · (Edited)
Hi guys, I hope this is right place for this.

Lately none of my hand loads have been anywhere near the published velocities for that particular load. For example, for my 30-06 I worked up a load from the Nosler 9th edition manual using their 150 grain E-tip. I used 57.5 grains of IMR 4350 with a case over ll length of 3.300", using CCI Br2 primers, case trimmed to lengh 2.484". I'm shooting it out of a Thompson Center Icon Classic, 24" barrel with the 5r rifling. I put each shell through a Lee factory crimp as well and my tolerances are within 0.0005 of the c.o.a.l. using a digital caliper. It should be around 2880/2900 fps but as you can kind of see in the picture, I barely got 2775. I was using a F1 Master Chronograph 10' away from the barrel. It was 57 out, sunny, no wind and with 72% humidity at an altitude of 2,200 feet above sea level. What am I doing wrong? Should Io seat them lower? I mean the grouping at 100m is stellar but at this velocity its basically a long .308 win. Thanks for your input.

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18122313.jpg

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18074029.jpg

Could be several things at work here. First, I would set up the Chrony at 15 ft., just to make sure muzzle blast isn't causing false readings. I've got the same one and it works very well at 15.

Next, what rifle did they test their loads in? There could easily be 100 fps difference even between two identical rifles with the same barrel and twist. The Hornady #9 manual shows about the same fps as Nosler for their various 150 gr. bullets from a 24" Model 70 1:10 twist. If you're not getting any pressure signs at 57.5, try working up to 59 to see if the velocity improves. You may just have a 'slow' barrel. If you can get your hands on some CCI-250 primers, give them a try. The BR2 is a bit on the mild side. The hotter mag primer may boost your initial pressure for a better burn. If you do that, be sure to drop back a couple grains and work back up.

You're not doing anything wrong. 3.33" is what I load my '06 at for the M1, and same for my .280 Rem Ruger 77 bolt. Frankly, though, accuracy is far more important than velocity, and if the group you showed is typical of that load, I'd leave it alone.
 
#3 ·
Maybe your bore is a bit different than the test barrel.

I share a few of the same loads in two of my 30-06s, one rifle is always 100fps or more faster. The bores are the same length and slug very close, the lands are thinner on the faster bore.

My Hornady 7th Edition says for a 30-06 with a 26 inch barrel to expect about 2850fps with that charge weight. Your velocity sounds about right.
 
#9 ·
there must be alot of slow barrels out there.

My Marlin XL-7 in 30-06 sends a 165gr SST out the barrel at 2850fps with 56grs of IMR4350 and a CCI200 primer. That is measured at 15' and using a 22" barrel.

A 150gr bullet out of a 30-06 should be closer to 3000fps, not 2800fps. Heck, my 18" remington 750 in 308 win shoots 150gr bullets at 2700fps with little trouble. 41grs of 3031 I do believe.
 
#4 ·
1) No two chronys are going to record exactly the same.

2) Velocity loss from muzzle to 10' or 15' needs to be compensated for.

3) As stated above, you may have a "slow" barrel compared to the Nosler testing rig.

4) Your powder and primer lots will surely differ from those used at the time by Nosler.

5) If grouping is more than satisfactory, why mess with a good thing?
 
#5 · (Edited)
1. More generous chamber, throat and barrel dimensions can reduce pressure and velocity.

Tools wear and a chamber and or barrel made with new tooling will have large dimensions the same items made with older tooling.

2. Most loads are developed at standard temps of 70 degrees. You're probably losing around 10 fps at 57 degrees with IMR 4350, so it's noticeable but not significant.

3. I agree that setting the chronograph farther away is a better practice as it avoids the potential for the muzzle blast to trip the first sensor, but in most cases that won't be an issue at 10' unless you're using black powder. I set mine up so that the cord runs from the bench to the chronograph in a long arc that just touches the ground. I can't tell you what that distance is exactly, but it's consistent each and every time i set it up.

4. You will want to correct the measured velocity to a muzzle velocity but it's not large. For the load in question the velocity loss from the muzzle to a chronograph at 15' will be about 10 fps.

5. Powder lots vary and 50-100 fps difference in a given charge weight in a 30-06 sized case with 50-60 grain charge weights would not be unexpected. Way too many people regard the stated charge in a loading manual as being meaningful when it's really not.

It's made worse when they read a website that gives the nominal charge for military specification ammo, for example .30-06 M2 Ball with a 150 gr FMJ and 46.5 gr of IMR 4895 and a velocity of 2,740 fps, and then fail to understand a) what "nominal" means, and b) that the critical number here is the velocity of the load, not the powder charge. The actual charge weight for any given lot of IMR 4895 (or any other powder will be what it needs to be, and you'll load for velocity while watching for any signs of excess pressure. In some military calibers, especially 5.56mm NATO where the mil spec load was warm to start with and the chamber and throats were very generously cut, you may or may not be able to achieve a specified maximum velocity in your particular rifle. But that's also not real important as accuracy matters a lot more than velocity.

6. It's also largely irrelevant. For example, you're only getting 2775 fps with your 159 gr E-tip rather than 2880 fps, with a 300 yard zero it will make the following difference at 400 and 500 yards:

2775 fps:
Max mid range trajectory = +5.5" at 175 yards
400 yards = -12 low, 2064 fps, 1418 ft pounds
500 yards = -32" low, 1902 fps,1205 ft pounds

2880 fps
Max mid range trajectory = +5" at 175 yards
400 yards = -11" low, 2152 fps, 1543 ft pounds
500 yards = -30" low, 1987 fps, 1315 ft pounds

Basically, that loss of 105 fps means only 1" more drop at 400 yards and 2" more drop at 500 yards. That's equal to a 5 yard error in range estimation at those same distances, so it's not even on the top 10 list of things you need to worry about when shooting at those ranges.

Accuracy is far more important than velocity or energy in a .308-.30-06 class round and I would not fret over my .30-06 producing .308 velocities if you're getting MOA accuracy out of it with a hunting load.

And by the way I shoot a .308 anyway as they tend to be more accurate than a .30-06, as well as slightly more efficient. :)
 
#6 ·
Thanks for the input guys. According to Nosler, they use a 24" lilja barrel. The group shown is typical of that load, I shot 4, 3 shot groups (12 total) and they all averaged less than 0.4". I didn't know that barrels could be slow compared to others but a good point was brought up about one barrel's lands being thinner than another and I guess it makes sense, the less surface contact the less friction and faster the velocity. I have the CCI 250's I use for my brothers 300 wsm, but I thought your not supposed to use magnum primers in non magnum calibers?

Here's another pic of what this rifle is capable of producing.

http://i941.photobucket.com/albums/ad252/smeagdelphi/20130609_163852-2.jpg
 
#7 ·
Thanks for the input guys. According to Nosler, they use a 24" lilja barrel. The group shown is typical of that load, I shot 4, 3 shot groups (12 total) and they all averaged less than 0.4". I didn't know that barrels could be slow compared to others but a good point was brought up about one barrel's lands being thinner than another and I guess it makes sense, the less surface contact the less friction and faster the velocity. I have the CCI 250's I use for my brothers 300 wsm, but I thought your not supposed to use magnum primers in non magnum calibers?

Here's another pic of what this rifle is capable of producing.

http://i941.photobucket.com/albums/ad252/smeagdelphi/20130609_163852-2.jpg

Hodgdon 2014 manual has loading data just for the 30-06 with 150gr E-Tip. They don't list who's barrel there using but it's 24" long,1/10 twist,Win Cases,WLR primers.

This is from that manual

54gr/IMR-4350 @ 2744 max 57.5gr/IMR-4350 @ 2930fps.

Nosler data

55gr/IMR-4350 @ 2760 max 59gr/IMR-4350 @ 3000fps.

Hard to say on factory barrels.
 
#10 ·
Lot of good answers so far. I believe reloading manuals give the results that a particular technician found when he used the listed powder (prolly a different lot than yours) with the listed bullet (different lots may have slightly different ballistics) in a specific case (also different lots may have a slightly different alloy, capacity, etc.), with a specific primer (also different lots may not be exactly the same as those used by the technician) in a particular test fixture (some use universal receivers with barrels of unknown wear) on a particular day. Pretty difficult to duplicate exactly...
 
#11 ·
Who cares what the velocity is with groups under an inch at 100 yards, especially with Etips!!!

RJ
 
#13 ·
You don't have a clue if your chronograph is accurate. Without calibrating it, any reading is just that, a reading. Some numbers on a display. After you use it over a period of years, with a number of different guns, you might get a better feel for how accurate it is. But most of us will never know, because we can't calibrate them. That includes me.

If it is an accurate load.... who cares. I do agree with the suggestions to move it farther out. Muzzle blast will set them off, sometimes.
 
#17 ·
I can't calibrate my chronographs, but I can validate the results to a great extent, and it's the validity that matters.

For example, if I shoot over a chronograph and get a particular average velocity, then I should be able to predict the anticipated trajectory given the number of very good ballistics programs that are out there.

So if I get an average velocity with a low SD (and it's the ability to measure consistency that is one of the major advantages of a chronograph) then I should be able to expect a specific amount of drop at long range. Consequently on a calm day with more or less standard conditions, I can zero the rifle as a known distance, then increase the range to another know distance with the required sight correction and either get a series of hits near the point of aim, and validate the chronograph results, or find they are shooting consistently high or low, and invalidate the chronograph results.

----

This is of course also another back door argument for accuracy and consistency over velocity, as getting the rounds on target consistently is what matters, whether you are hunting or target shooting, and accuracy will help you do that, while an extra 100-150 fps makes very little difference, and is counterproductive if it comes at the expense of accuracy.
 
#14 ·
King4,

As MikeG says, it could be a chronograph thing ----

However it has been my experience that there are basically three groups of rifles as far as velocity goes.

The largest group by far are those who do not match published velocities many times falling short by 1 - 200fps or more.

The a smaller group are those that about match published data.

Then the smallest group are those that exceed published data all while showing no excessive pressure signs of any kind.

A few Speer manuals back, they had data for a 300Win Mag load that would make a velocity hounds blood run hot, but in real life in a rifle I had with a 26" barrel fell hundreds of fps slower.

I suspect that a number factors entered in here. Of course the barrel and chamber Speer was using, but maybe more importantly was the lot number of the powder they had.

I have seen velocity drop by nearly a 100fps with just a change in powder lot numbers.

So, as has already been said, if your rifle is grouping well you really have no issue to worry about. The critter will never know it was killed with a bullet moving slower then the published data.

Now, I think that the Chronographs are mostly close enough, and if over the same chronograph I am seeing consistent results with a given firearm on a given day and following shooting sessions, and also seeing velocities with different firearms that are running in the normal ranges of Slow, about on and fast velocities, and all on the same chronograph, I really feel it is more a firearm to firearm difference.

Look at it this way, knowing what you now know, think of the fun you will have when taking a friend out with his wiz bang super duper whatever and it shows velocities a couple hundred fps off the published data he was grooving on. Fun, been there and it is great fun watching the expressions.

Then you can explain the facts of life/reality to him, and if his rifle happens to be one of the fast ones, you can both marvel at the great results he got. Just don't bet any money on that happening.

Crusty Deary Ol'Coot
 
#15 ·
Back when chronographs cost as much a good used car, guys didn't have a clue if their ammo was getting the velocity claimed on the box or in their reloading manual. They grabbed some rounds, sighted in their rifle, shot at longer distances if they had the chance, and went hunting.

The difference in resultant trajectories between rounds going 2900fps and 3100fps is measured in tenths of an inch, at hunting distances of 300 yards or less. The difference in energy (which doesn't matter much anyway) is also nominal. So, don't get wrapped around the axle if your speed machine says your bullets are a little slower than "book"...load, shoot, hunt!
 
#18 ·
Here's some real world data that is so fresh, you can still smell the powder smoke. Its a good illustration of how expectations and manual data don't always line up with real numbers.

I spent most of the winter gathering information on loads for the .280 Remington. I used data from the 70's (Speer), Ken Waters Pet Loads book, loads from recent magazine tests, and the new Hornady #9. Knowing that factory ammo is downloaded for autoloaders like the Rem 742, I ended up doing a fair amount of guesstimating. Anyway, I came up with a set of ladder loads for 139, 150, and 162 gr. bullets. Yesterday was finally range day.

Since I was also using a new scope that hadn't been sighted in under fire, I used some old leftover 160 gr. loads from silhouette shooting days. Only took three rounds to adjust things sufficiently for testing.

The surprise was in just how far off my velocity estimates were. The old loads turned in speeds of 2950, which is at least 100 fps over what I was getting in my original .280 Ruger. The 139 gr. loads hit an average of 3112 fps, at least 200 over what I expected for the first rung of that ladder. The 150 gr. was only 75 fps over. The 162 gr. was about right at 2800 fps, but again only on the first rung.

So, what I found out was that I have a tight fast bore, with a slower twist than I expected. It really likes the 139 and 150 gr., but the 162 was just barely being stabilized. The barrel is a custom Douglas XX Air Gauge, but it could be had in several different twists. The usual twist in most .280 factory rifles is 1:9, but this one appears to be 1:12 which is a common twist for custom barrels and which won't handle the long heavy boattail spitzers. In contrast, the old 160 Speer sptizer flat base stabilized just fine leaving nice clean, round holes. They're shorter.

The end result is that I will have to reduce the charge at least a full grain on the 139 and 150 (they were pretty flat and had the beginnings of craters), have to use flat based 160 gr., and break down 20 rounds of ladder loads that are too hot to risk firing. That's OK though, as both of the lighter bullets gave decent groups even though this trip was mainly to find the top end in terms of pressure. It just turned out to be earlier than I expected.
 
  • Like
Reactions: Crusty Ol'Coot
#20 ·
I am going to play the devil's advocate, so take these comments with a grain of salt:

What if the increased velocity you're seeing is because of the slower twist, which does not impede the bullets as much in their travel down the bore? Did you see any indications of excessive pressure? Maybe what you're seeing is perfectly normal velocity from a 1:12 twist barrel? Maybe your bore isn't tight or fast at all?

The interdependent relationships that exist between case capacity, bullet weight, powder burn rate, chamber size, bore diameter and rate-of-twist, among others, makes it nigh impossible to predict just how fast a given load combination will be from a specific cartridge. All we can really say is if you're shooting great groups, test 'em at longer distances and then go shoot some stuff! :)
 
#23 ·
I agree with a lot that has been suggested. I would use CCI200 primers and skip the crimp.
How fast do you want to go? The Cartridges of The World lists a heavier charge of IMR4350 to achieve 3000 for a 150gr. Did you get any pressure signs at the 57.5 load you made?
You are just shy of 2800fps and only 200 away from 3000 which I would say is tops, so the difference could be in your particular barrel.
I did not read all the previous suggestions but those are my thoughts. I myself would be tickled with 2800 with stellar accuracy, but that is just me. If you really need to get 3,000 you might need to get a different barrel or different gun or maybe even a magnum. Good luck, let us know what you decided. Jim
 
  • Like
Reactions: Crusty Ol'Coot
#25 ·
One day at the range, I set my chronograph up a little too close to the bench. Factory 100gr. bullets in the .257 Weatherby clocked a little over 5,000fps.... Roy would be proud :D

Setting it up a few feet farther out got some more reasonable velocities. I've seen a change in 400 or so feet per second from moving the chronograph a few feet on other occasions.

Not saying they are all that sensitive, but .... it pays to check, and set them up as far from the bench as practical (depending on what you are shooting of course).

The more you use a measuring device, the more you question how to ensure it is accurate.
 
#27 · (Edited)
Over the years, I have often run into powder lots that have tremendous velocity variations, with all other factors being identical, simply because they are often from different plants, from different countries. This was especially true with slow burning powders such as H-4831 and IMR-4350. On one occasion, I had just worked up three individual loads for my wife's, brother in law, and my own .27 Sako rifles, that were going on a Wyoming hunt. The three rifles varied slightly within 75 fps. of each other, but were all delivering in excess of 3150 fps. with approximately 60 gr. of H-4831 for our 130 grain Noslers. After testing, we ran out of that pound of powder and purchased a large canister to load up for the trip. On testing, we were shocked to see that our velocities had dropped to averaging 2750 fps., which wasn't even close!!! We were devastated. Case capacity was already compressed. One was made in Australia, and the other was Scotland. I don't recall which, off-hand (I have records on this somewhere). After several dozen calls to every store in the phone book, we found a retailer who had my old lot on hand, and we bought an 8 pounder, and we were back to our expected velocities. Do you know what it's like to ask a kid on the other end of the phone to cooperate and read off lot numbers of powder on his shelf? The moral to the story is that the making of powder is a marvelous science, but not a precise one. It taught me a great lesson. The velocity of a lot of powder is relevant to that lot of powder, and not necessarily to any other. I don't find such extraordinary velocity differences to be normal in the industry, by any means, and I can certainly attest that most powders perform withing a percentage point or two of the other of a given brand and number, but I do find that variations tend to surface more with slower burning powders, which are more sensitive to anything that affects pressure; barrel diameter, primer type, seating depth, etc.

Any time you are within 100 fps. of a published velocity with the same barrel length and seating depth, you are on the mark, and you can call any variation entirely inconsequential. Remember too that seating depth can be very close to the lands of one gun, while providing a long jump in another. These variations are the reason that chronographs have become popular. There is no such thing as duplicating specifications from one gun to another. Did I mention primers? That alone can make a difference of 100 fps. or MORE, from brand to brand, lot to lot. The 75 fps differences that the three otherwise identical and beautifully crafted Sako rifles delivered is a significant indicator that extremely subtle variations in throat, chamber size, and barrel dimension can affect velocity, even with identical loads. Add that 75 fps. to another 100 fps for primers and maybe another 100 fps for powder, and you can see what can occur, statistically. Published velocities are not and are never claimed to be expected velocities.

Don't concern yourself about velocity variations in the order of 100 fps., anyway. The differences in drop are negligible. Simply sight in with the end result, and be good to go.
 
  • Like
Reactions: Crusty Ol'Coot
#28 · (Edited)
You've gotten some excellent advice from others on this thread, but I should add that I have done a lot of "load-testing" in the past on my various center-fire rifles and found that the IMR powders were giving me less and less muzzle velocity, especially as the air temperature drops and/or if different lots of powder are used.

As an example, in my Model 99's .300 Savage, a near maximum load gave me an average of 2713 fps or there abouts. Two years later, I bought a new can of IMR4895 and the same load only gave me 2685 at the same temperature (85º F).

Later that year, just before deer season, I check the same load again at about 30º F and got only 2630 fps due to the outside air temperature.

A few years later, I bought still another can of IMR4895 and was SHOCKED when the same load gave me a mere 2548 fps on a 30º day... and this was a load that yielded 2685 fps only a few years before at 85º and 2630 fps at the same 30º with the SAME powder load and the same other components except the slower velocity was with the newer lot of IMR4895 and a different "lot" of powder as GunBlue pointed out (just above my post) !~!~!

I happened to have some hunting loads that were loaded with the older 4-year-old IMR4895 powder that I had taken along to the rifle range in my shooting box, so I chronographed them and, much to my surprise, they still yielded the 2630 fps that they have given me 4 years before. It was a "duplicate" 30º day... the same air temperature that yielded 2630 fps with the "old" IMR4895 was now yielding only 2548 fps at the SAME air temperature using the same load except for the use of the newer lot of IMR4895!!!

Obviously, the SAME amount of the SAME brand and type of IMR powder (IMR4895) in my .300 Savage caliber rifle was NOT yielding the SAME muzzle velocity as former lots of the SAME powder had given me... and the older lot still chronographed at about 2630 fps (2632 fps on the re-check) while the new IMR powder loads yielded a mere 2548 fps. I also noted that the newer IMR4895 came in a different type of container and was made in CANADA, not in the USA at IMR's former powder plant. I also noted that the newest IMR4895 came in a "different" PLASTIC powder JUG, not in the familiar METAL powder CAN as it had always come for the previous 30 or 40 years.

I "switched" to Hodgdon's H4895 and found it was one of Hodgdon's "EXTREME" powders meaning it gave the SAME muzzle velocity regardless of outside air temperature whereas the IMR powder not only yielded LESS M.V. than previously with the SAME powder amount used, but the IMR powder was also effected by air temperature... I.E., a lower air temperature caused the IMR powder to NOT give as high a muzzle velocity whereas the H4895 gave the SAME muzzle velocity regardless of the air temperature. But I also became aware that the older lots of IMR4895 yielded HIGHER muzzle velocities than the newer lots of the SAME IMR powder (IMR4895).

It is quite possible that when IMR changed hands (I understand they were bought out), the new corporate owner changed the formula which was used to manufacture the IMR powders including the IMR powder you're using.

In addition, I suggest you see (if possible) at what TEMPERATURE your reloading manual indicates their muzzle velocities were obtained. With IMR powders, as the temperature goes down, so does their muzzle velocities and THAT may be your "problem".

Suspecting Hodgdon's claim might not be true, I tested the H4895 loads during different air temperatures from 90º F down to less than 20ºF... and the muzzle velocity remained at 2630-2635 fps, very much in the same velocity range as it had at 80º+ when I developed the load.

I also suggest you should "look at" (and "try") some Hodgdon H4350 rifle powder using the SAME additional components you're currently using with the IMR4350 and check the results.

However, that said... I must agree with others who posted on this thread. Your and your rifle's accuracy is EXCELLENT... and the game will never know the "difference" in a 100 or 150 fps muzzle velocity of the bullet. Therefore, I'd "go" with watcha gots... it doesn't get much better than that, my friend since "accuracy" in bullet placement is MUCH more important than a few hundred fps in velocity.

And, as suggest here by RIFTER and others (see above), I'd move your chronograph BACK to 15 feet from the rifle's muzzle. At 10 feet, you very likely may be getting some "muzzle blast" interfering with your Chrony's readings. My Chrony's instructions suggest the Chrony should be placed 15 feet from the muzzle. :)


Strength & Honor...

Ron T.
 
#36 ·
You've brought up something I've suspected for many years. The chemistry on powders. It APPEARS that the manufacturers can and do alter that chemistry now and again. Obviously it can be altered, since that is one of THE major ways to make a powder perform differently for different purposes. It APPEARS that as long as the resulting powder doesn't produce MORE pressure than its former version, within limits set by the manufacturers, then they'll send it out as it's old version. When it gets altered to be "hotter" it gets a new designation. This is obviously a very simplified version, and not a documented fact by any means. But real world events and occurences would seem to substantiate my opinion. QC problem? Not long as they DO the QC and catch it before anything dangerous occurs. All it would mean is a little less recoil, and likely a slightly lower point of impact.
All manufacturing has tolerances. Your case seems to indicate that powder manufacturers, at least this one, seem to be sliding down on those tolerances. Why, I have no way of knowing.:confused:
 
#29 ·
Muzzle to Chronograph Distance and Powder-Charge

King4 wrote, " It should be around 2880/2900 fps but as you can kind of see in the picture, I barely got 2775. I was using a F1 Master Chronograph 10' away from the barrel.".

That's a bit close to the muzzle. What can happen is the muzzle blast which behaves like a very high-speed bullet with short range triggers the clock but the bullet which arrives later stops the clock. It's also possible that the muzzle blast starts and stops the clock but that should give really weird readings. The muzzle blast starts out nearly twice the speed of the bullet but may be near the speed of sound by the time it reaches the chronograph. I would suggest changing to 15 feet as others recommended.

I was testing shotgun slugs one bad day and set up very close to get things done quickly... I was reading speed of sound for a very hot load that hurt my shoulder... The manuals predicted ~1600 ft/s +

There's nothing wrong with .308 Win for nearly any big game around here. You only get a bit more easy range with higher velocity. More important for hunting is the accuracy and energy delivered to the target. Higher speed bullets lose energy faster so the increase in range is minimal even for a magnum.

If you really do need a bit more velocity, you might check the distance to the rifling and seat the bullet out a bit further with a slightly higher charge of powder. In that length of barrel, the more powder you start, the faster the bullet will depart. If you lose accuracy doing that, stick with what you have. I usually just bump the neck and seat a bullet out long and chamber a dummy round. The rifling should seat the bullet deeper. Then measure LOA. There's no harm in seating out further than spec if you work up charges gradually and the rounds feed. You could also use a bullet with higher BC or lighter weight, if that's OK with your target. You're already getting wonderful performance and velocity is not the goal.

Another variable might be the primers. I don't know BR2s. Are they more uniform and lighter than regular? You could work up a load with a different primer. A heavy charge of slow powder may need a hotter primer to get going quicker. A test of different primers with identical charges shows BR2 on the light side but with a definite advantage in accuracy. Perhaps a bit more powder is the answer. see The Effects Of Different Primers On The Load
 
#30 ·
You are in the park. Don't be disappointed. that is good shooting for a light weight rig and respectable velocity. If you want higher numbers, go to a magnum, but I don't recommenced that. You will only be chasing another rainbow at dangerous pressures.
 
#31 ·
Several years back, I found the most accurate load for my Model 70 .30-06 was a 165 Nosler Ballistic Tips loaded down to .308 levels with H414. It was a good 200-250 fps slower than max load data and shot cloverleaf groups. While everyone else was complaining about ballistic tips blowing up, I was having no problems shooting clean through every deer I shot. I even took a front quartering shot through the shoulder of a real nice big bodied buck with quick lethal results. The point is, as others have mentioned, velocity can be over-rated. I cleanly killed dozens of deer with that load at various ranges. The deer never realized how "slow" my super sonic bullets were. The truth be told, the BT's terminal performance would surely not have been as good if I was up at max levels.

On the flip side of the coin, I have a 7mm WSM with factory load performance that I can't come close to duplicating with handloads. Since it's my open country and bean field gun, I find that a little irritating. The .30-06 mentioned above was downloaded by choice. I could have loaded it hotter and have with other loads. On the 7mm WSM, it's not by choice and it quite irritating given the cost of factory magnum ammo.
 
#32 ·
Hi guys, I hope this is right place for this.

Lately none of my hand loads have been anywhere near the published velocities for that particular load. For example, for my 30-06 I worked up a load from the Nosler 9th edition manual using their 150 grain E-tip. I used 57.5 grains of IMR 4350 with a case over ll length of 3.300", using CCI Br2 primers, case trimmed to lengh 2.484". I'm shooting it out of a Thompson Center Icon Classic, 24" barrel with the 5r rifling. I put each shell through a Lee factory crimp as well and my tolerances are within 0.0005 of the c.o.a.l. using a digital caliper. It should be around 2880/2900 fps but as you can kind of see in the picture, I barely got 2775. I was using a F1 Master Chronograph 10' away from the barrel. It was 57 out, sunny, no wind and with 72% humidity at an altitude of 2,200 feet above sea level. What am I doing wrong? Should Io seat them lower? I mean the grouping at 100m is stellar but at this velocity its basically a long .308 win. Thanks for your input.

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18122313.jpg

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18074029.jpg
I understand your question, and the reason for it. But! If it's hitting where you put it, consistently, that velocity behind that bullet is plenty to get meat. And if your only punching targets, if it is accurate, why push for more. You are correct in the statement that it is in effect, a .308 Win load, towards the fast end . That is about what I shoot out of my .308s. 168 grain Nosler Ballistic Tips, at about 2700 fps is my favorite load. I eat a lot of venison off that. Have for many years. So while I do understand your curiosity about why the difference between a stated load and your actual velocity, what you actually have ain't gathering flies, by any means.
In other words, if it aint broke, why fix it?
 
#35 ·
Hi guys, I hope this is right place for this.

Lately none of my hand loads have been anywhere near the published velocities for that particular load. For example, for my 30-06 I worked up a load from the Nosler 9th edition manual using their 150 grain E-tip. I used 57.5 grains of IMR 4350 with a case over ll length of 3.300", using CCI Br2 primers, case trimmed to lengh 2.484". I'm shooting it out of a Thompson Center Icon Classic, 24" barrel with the 5r rifling. I put each shell through a Lee factory crimp as well and my tolerances are within 0.0005 of the c.o.a.l. using a digital caliper. It should be around 2880/2900 fps but as you can kind of see in the picture, I barely got 2775. I was using a F1 Master Chronograph 10' away from the barrel. It was 57 out, sunny, no wind and with 72% humidity at an altitude of 2,200 feet above sea level. What am I doing wrong? Should Io seat them lower? I mean the grouping at 100m is stellar but at this velocity its basically a long .308 win. Thanks for your input.

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18122313.jpg

http://i941.photobucket.com/albums/ad252/smeagdelphi/2014-05-18074029.jpg
Another thought just occurred to me. A few years back, I came upon something I had wanted for many years in my youth. A 300 Win Mag. Took it home, and worked up some loads for it, using the same bullets I shoot out of my .308s. Funny thing happened. While the .308s are devastating on the central Texas whitetails, and the extra 300+ fps out of the 300 Win Mags longer case certainly didn't make it any LESS lethal , a funny thing happened to the wound. Where the .308 goes in the chest cavity and blows up everything in there, the 300 punched a golf ball sized hole through the other side. Just that seemingly small velocity change made it actually a less messy wound channel. Same result, dead deer. But it always surprised me to see that thru hole instead of often times no thru hole from the .308, just a total wreck inside the chest cavity. And this was from several deer, of different sizes and different angles, different shot circumstances altogether. I would have guessed before having shot those shots that the extra velocity would make an even more devastating wound cavity.
I've actually wanted to bring this up on the forum sometime, but it never occurs to me when I'm not otherwise occupied. The experience on display here would make an interesting avenue to explore this phenomena.
So in actuality, your slightly lower velocity MIGHT actually make a difference in terminal performance. And by terminal, I mean terminal to the game.
Your actual mileage may vary.:)
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top