[chase.2]

I'm new to hand loading but have done alot of reading on it and just came home from the range where I was testing some "working up" loads in my Browning A-bolt .243 win. Here is what I ran:
90gr Speer spitzer, Federal brass, WinLR primers and 43gr to 47gr of Reloader 19, working up in one grain increments. I observed no excessive pressure signs through this range of loads.

90gr Speer spitzer, Federal brass, WinLR primers and 40gr to 45gr of IMR-4350 working up in one grain increments. At the 45gr mark. one sign of excess pressure was observed; a shiny spot on the case head from where the brass expanded into the ejector-pin hole. Also, something very strange, at 43gr the primers stopped being flat and went back to round shoulders like a reduced load.

100gr Siera spitzer, win brass, WinLR primers and 43gr to 46gr of Reloader 19 in 1/2 grain increments. Other than flatter primers, (and I still don't know how flat is too flat) I didn't see any signs of excess pressure.

continue on next post...

 

[chase.2]

pressure signs continued...

...100gr Siera spitzer, win brass, WinLR primers and 43gr to 45gr of IMR-4350 working up in one grain increments. At the 45 grain mark I got the same ejector-pin shiny spot on the case head.

All of my loads were at a C.O.A.L. of 2.650. My load data was from Siera, Lee and Lyman manuals. However, all of my loads exceeded the manuals by one or two grains.
Now to the point. I know I need reduced the loads that show signs of excess pressure but I'm not shure by how much. These tests were to find the highest practical velocity for my rifle and I know the manuals can be a bit conservative.

I am open to all types of comments, advice or criticism.

 

[ribbonstone]

Don't think manuals are conservative. A larger than standard chamber, longer throat, larger bore diameter can work to decrease pressure..smaller can increase it...so each rifle has some variability, but do not believe the manuals are made to be conservative. Believe there measure of pressure is accurate for their test barrel, it just might be different in your barrel (and as likely to be over pressure as under pressure).

Basically, if the case looks beat-up after 5 reloads, the load is probably too hot for that rifle....if it looks good after 7 reloads, it's probably a decent max. load.


You aren't alone in reading primers...it's like reading tea leaves. Even at the same pressure, if the flash holes of one case are a bit larger, the primer takes more of a beating. If the case sets back more easily (cleaner case...oil in chamber... smoother chamber..whatever) the primers are likely to look different than when a case tends to set back later in the firing cycle.

Wouldn't just look at the bullet weight, would look at bearing area and bullet construction. The more bullet that rubs the barrel, the higher the pressure, even if the bullet is slightly lighter.

 

[MikeG]

I've had factory loads leave the bright circle on the case head and hard bolt lift. Culprit was a rough bore, but don't push your luck. Those pressure signs are there to keep the bolt out of your forehead....

 

[chase.2]

Although it is possible there are flaws with my gun, I doubt it. I am the original owner and only has about 100 rounds through it, plus I have managed 3/8" groups at 100 yards with some lighter loads.

As far as group sizes go, my Browning A-bolt has the BOSS so my intended goal was to find a fast load and then tune the BOSS to make it accurate. For example, the above 3/8" groups are at a BOSS setting of 6.0 but become 1 1/2" at a setting of 5.0

I went back over my source data and the Lee book shows a max 43gr of IMR-4350 with 90gr jacketed whereas Lyman manual shows 45gr IMR-4350 max for the same weight bullet but it's a boat tail, perhaps that's the reason for the increased load?

 

[Darkker]

I also am not a fan of reloading by the book in terms of COL. As was re-proven to me with the last gun purchase of mine. I have a 25-06 that has a VERY short throat. My Hornady books list COL, and IF I were to seat the three bullets I've loaded to the listed distances; I'd jammed the bullets into the lands.

 

[Ridgerunner665]

I have exceeded your Reloder 19 loads in a 243 (more than one 243 actually) by enough to make some people wonder about my sanity...no problems in my guns, but they all have long throats. (Remingtons)

All guns, barrels, and chambers vary...learn how much is too much primer flattening, measure case head expansion and check it against the expansion of a known pressure tested load (factory ammo) fired in the same rifle,.

 

[chase.2]

cvc944. Read the OCW method and it seems hard to apply this method to a BOSS rifle. Maybe somebody here has done it and knows how?

BTW, thanks for the advice everybody!

 

[chase.2]

ridgerunner, it is worth noting that only IMR-4350 showed excess pressure signs and not Reloader 19.

 

[broom_jm]

Chase,

I would respectfully submit that the "goal" in reloading is not to obtain the absolute highest velocity, but rather to find the most accurate "safe" load that your gun will shoot. Any level of flattening, in your primers is a sign. Then next sign may be a blown case or pieces of gun in your head. An additional 50, 100, even 200fps means so little, under field conditions, that it simply isn't worth 2nd guessing the load manuals to get a little more speed. Those little 100gr bullets, at ~ 3000fps, will do terrible things to varmints up to and including deer. Why ask for more than that?

If you've got a safe book load that shoots 3/8" groups, and the (measured) velocity is acceptable, use your ballistics program to calculate drop and windage tables. Then, after confirming that load's accuracy is repeatable, put together 50 or so, and you're done, mission accomplished!

 

[ranger335v]

excessive pressure .243 win
<HR style="COLOR: #1d4976" SIZE=1><!-- / icon and title --><!-- message -->I'm new to hand loading but have done alot of reading on it and just came home from the range where I was testing some "working up" loads...However, all of my loads exceeded the manuals by one or two grains.


Let me get this straight: You are new to reloading but have done a lot of reading. So, you started at book max and then worked up?

My God, do much of that and we'll have a new candidate for the Darwin Awards!

 

[Rocky Raab]

I stopped reading at "one or two grains" over max. A new reloader who utterly ignores all the wise advice printed in load manuals is probably not going to listen to me, either.

I don't mean that as a flame, but that's what I've observed over the decades.

 

[kdub]

To be indulgent to a new reloader - in my 50 odd years of reloading, I've found the best combination for accuracy and velocity is usually just a bit under the maximum listed in the manuals. Realizing the recommendations vary from manual to manual, I stick with one that I value most - the Lyman manual. They show in detail the type of firing mechanism used, the bullet brand for a given weight, primer brand, etc.

These folks have spent more money, time and resources than I'll ever have to develop these listings, so I pay pretty close attention to them. Have tried bumping the envelope when much younger and found the results were never satisfactory.

 

[jwp475]

Although it is possible there are flaws with my gun, I doubt it. I am the original owner and only has about 100 rounds through it, plus I have managed 3/8" groups at 100 yards with some lighter loads.

As far as group sizes go, my Browning A-bolt has the BOSS so my intended goal was to find a fast load and then tune the BOSS to make it accurate. For example, the above 3/8" groups are at a BOSS setting of 6.0 but become 1 1/2" at a setting of 5.0

I went back over my source data and the Lee book shows a max 43gr of IMR-4350 with 90gr jacketed whereas Lyman manual shows 45gr IMR-4350 max for the same weight bullet but it's a boat tail, perhaps that's the reason for the increased load?

You realy do not understand, original owner makes no difference as to a rough bore or not with an over the counter factory rile.
Next the 243 Win is a chambering that demonstartes unusual, high unexplained pressure spike. Also it is not possiable to determine pressure by case observation and the reloading manuels are not soft. They are at the SAAMI max allowed average with the components used during testing. You are indeed threading on dangerous grounds

 

[MZ5]

cvc944. Read the OCW method and it seems hard to apply this method to a BOSS rifle. Maybe somebody here has done it and knows how?

The OCW method is the single best, most efficient way to systematically find outstanding loads that work just in a rifle, but across most all rifles in that chambering, IME. Having said that, you are correct that it would be ludicrously expensive to conduct ANY reloading accuracy work-up in a BOSS rifle, if you approach it in the traditional work-up fashion/mentality.

I have a BOSS-equipped rifle, and here is what I think:

What one must understand is that, in a 'regular' rifle, one has a static or 'fixed' tool, and one must adjust the 'work' (the load) to meet the needs/condition of the tool. With the BOSS, one has an adjustable tool, and thus can simply choose the 'work' (the load) one prefers, and adjust the tool to it.

The BOSS is intended to give the flexibility and adjustability of handloading to the shooter who only buys factory ammunition. Don't think it'll give you 0.25" groups with anything you throw at it, though, because it almost certainly won't. However, you have considerably more room to get anywhere from decent to excellent ammo from nearly anything you choose.

My recommendation is to stay within factory manuals' loads. Choose one you like (perhaps a bit down from book max, as was suggested by kdub), with a bullet you like, a powder you like and/or find easy to work with, and then tune the BOSS to that load. If you just can't get it to shoot as well as you want, adjust the powder charge a bit and try again.

 

[Nalgi]

I agree! what are you doing?

playing around like that? As the other old sages said, its about accuracy not velocity. Start with the starting load and LEARN to reload and LEARN what your rifle likes and doesnt like.

My wife and I have identicle Mod. 700; 300 WSM but they like completely different loads and overall lengths.

Starting with a compressed load and noting the effects of excessive pressure doesnt tell me read very much after the part that says CAUTION:

(I'm being hard on you because I dont want to see you get hurt)

 

[chase.2]

Thank you all. As I said, I accept criticism.

My first post has discrepancies. Only one of my loads exceeded book maximums.

For 100 grain spitzer, IMR-4350, Lyman shows 39.5gr max.
Sieara shows 41.7gr max.
Lee shows 42gr max.
my max 45gr.
I am willing to accept that this was foolish.
Altho I started at 43gr for this batch, my first batch (a few weaks ago) I started at 38.2gr which is near Sieara's minim load and worked up to 42gr. Sieara's max is at 43gr. I could see no difference in the primers from bottom to top of this range.

For 90 grain spitzer, IMR-4350.
Lee shows 43gr max.
Sieara shows 41.8gr max.
Lyman shows 45gr max.
my max 45gr.

For 90gr spitzer Reloader 19.
Lee has no listing.
Sieara shows 43.8gr max.
Lyman shows 47.3gr max.
my max 47gr.
Is Sieara being conservative? I'm not shure.

...and then, hmm, I'm not shure why I went so high with 100 grain spitzer and Reloader 19. I must have read my books wrong.

Continue on next post....

 

[chase.2]

Seeing the sometimes wide range of loads book to book, had lead me to assume one of two things; either a given book is conservative or the equipment the laboratories use gave different results. To be honest, I got the notion to exceeded book maximums from my employer (a hand loader of some 20 years) when he shook his head in a casual way saying "I always go a few grains over max".

I will guess that there is over 1000 years of combined hand loading experience at this forum, so I take my lashings, learn my lesson and stick to the books!

Thankfully,
Chase.

 

[chase.2]

One thing I have not read or herd until this thred is that it is possible to over load with no signs of excess pressure present.

 

[big dan]

the thing to keep in mind is that the primers aren't gonna change shape until the loads get hotter, you've gotta remember that they are designed to work at the cartridges recommended max loading (sammi operating pressure) so they will look normal until they are overly stressed. i take the approach that if i am getting a noticable change in the appearance of the primer i am basically maxed out. if you have access to it take a look at page 61 of the 49th edition of the lyman handbook, there is an excellent picture of the way a primer should look after being fired as well as how it should not look! also if you have access to an accurate arms manual, 2nd edition, there is an excellent article in there that discusses the folly of more powder, ie going over maximum. it too is a good read.