Hello,

Steve and I just purchased some of the new Sierra 135 grain bullets but after calling Sierra, they had no suggestions other than use the data for 150 gr. bullets. After thinking about their suggestion, I thought that by using the loading data for a 130 gr. bullet and data for a 140 gr. bullet and splitting the difference that I might find a good safe load. I came up with 46 grains as a starting point. But to be safe I thought I would check with some of you who might have had a similar problem before.So my question is, have any of you loaded this new bullet yet and if so, what have you found to be an accurate loading? Or do any of you have experience with coming up with new loads for new bullets? I plan on using Win. 748 powder.

Thanks in advance for any help you can give me with this.

longrangehunter

What caliber is the bullet?

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And in what cartridge?

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It looks to me like Sierra makes four 135 grain bullets. A .277" MatchKing, a .308" MatchKing, a .308" ProHunter for single-shot pistols, and a .400" SportsMaster for pistol.

I think the newest is the .308 ProHunter, because they don't have a picture of it up on their web site. We still need to know the chambering, though. Except for the .277, 748 is going to be a bit slow for a bullet this light. Something like Reloader 10X is probably a better choice for the .30's. Maybe even IMR 4198? It depends on the barrel length, as well as the chambering. Especially if this is a pistol?

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OOPS! Sorry about that! I neglected to state the caliber and the cartridge! For some of you who know me, It's that darn medicine again. Considering my age it could even be a bit of that as well? :-) BTW, kdub, the little face with the sad frown is perfect considering the goof!

Caliber .30 and .308 cartridge. Using Federal cases with either Federal or CCI primers. unclenick, it is that new .30 caliber match bullet that Sierra makes that I am asking about. I gather from what you wrote that my choice of powders is too slow for the bullet weight. Thanks for the advice! I do have some IMR 4198 so what loading do you recommend for starting? Oh yes, I almost forgot. I am using this bullet in my .308 police rifle which is now being used for groundhog hunting! Several folks have stated that the caliber is all wrong for what I am doing, but using the 125 grain Nosler ballsitic tip ( Spitzer ) bullet loaded with Win 748 loaded to 3000 fps it does great out to 350 yards and sometimes a bit further. But Steve and I love to experiment with loads and new bullets in the hope that we can get a slightly heavier bullet that will handle light winds a bit better. We tried the new Barnes bullet in 140 grains but frankly neither of us have much faith in the accuracy so far. The best I can do with it after a lot of changes is 1 1/4 inches at 100 which just doesn't get it at long ranges. I have shot several groups that measured .460 at 100 yards, with the 125 grain bullet which if my math is correct comes out to just over 1 7/8 inches at 400 yards. IF the shot is perfect I can still hit the ground hogs head at that range. So I usually don't shoot much over 300 to 350 yards unless the GH stands up! We have both made 400 yard shots and been sucessful with them but it is ify at best unless a full target is exposed at that range.

That is why we are experimenting with heavier bullets. BTW, while I am asking, on the 125 grain Nosler, do you think a faster powder would make any real difference? The idea of using the match bullet was Steve's. Personally I like the results we have been getting with the 125 grain Nosler. Expansion is phenomenal and the accuracy is nothing to sneeze at. Frankly, considering the under half inch MOA which translates to under 2 inches at 400 yds, I doubt we will get much if any improvement on accuracy but maybe the extra weight will help a little on windy days. I have gotten used to the Mil dot reticle and also use a Mil Dot Master with my ballistics table written on a small card taped to the Mil dot's plastic cover, so windage is not really a problem either unless it is really windy. In which case we might as well be fishing!

Thanks for any advice you can give us on the new bullet loading. BTW, one more question. Would a heavier bullet, say a 150 grains or so, with good expansion qualities, give us any more range? Steve is looking for more distance, but I think 400 yards is about the limit considering our target size and caliber.

Thanks! longrangehunter

In the past, Sierrra has been the most helpful company I've dealt with...just give them a call and ask.
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Checked...they still run their 1-800 toll free service.
http://www.sierrabullets.com/index.c...on=techservice

This post brings up a question. What bullets get affected more by wind, Slow ones or light ones?

With my .223 running 55 gr. Vmaxs it not unusual to compensate 12 inches or more due to wind drift. When shooting the 22-250 with the same bullet it was similar although it was a couple hundred FPS faster. Doping the wind is part of the fun, beside it would make a dent in days you could shoot if waiting for no wind in SD.

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Monty F,

For a given bullet, faster works a little better, but not as much as you'd think. The amount of wind drift is proportional to the difference in time it would take for the bullet to arrive in a vacuum (no drag) and the time it takes in air. If you look at drag functions, once you are well above the transonic range, they drop off a little as velocity increases. In other words, as the bullet goes from, say, 2000 fps to 300 fps the closest match they have to the old G1 ballistic coefficient (B.C.) gets bigger. You can see this by looking on Sierra's web site for their match bullet B.C.'s. The are in velocity ranges, and the higher the range, the bigger the B.C. The drift reduction you get will be inversely proportional to that number.

For a given shape and caliber, heavier bullets also have higher G1 B.C.'s because of their greater sectional density, but you can't usually drive them as fast. That's the trade-off. Precision Shooting had an article last year in which the author shot .223 with progressively heavier bullets at 1000 yards. It's long range performance peaked with 80 grain VLD shapes, singly-loaded. The 90 grain bullets took up just enough additional powder space that, even though they had higher B.C.'s, they just couldn't be driven to high enough muzzle velocity to catch up to the 80's. If you had an infinite bullet selection, for any given chambering, you will find a peak bullet weight and shape for best performance at any particular range.


Longrangehunter,

The Noslers have a reputation for working well in some guns and not in others. If you found a good load with it in your gun, you may have trouble improving on it. The hollow points in match bullets are an artifact of the jacket cups being formed first, but are not designed to expand. That is why the military can use the 175 grain Sierra MatchKing in the M118LR sniper ammunition without violating the Hague Convention agreement on destructive bullets.

However, for long range, a boattail design will have higher G1 B.C.'s, so wind drift should be reduced. You will want to find a sweet spot load for accuracy. If you give me your barrel length (22"?) and the water capacity of one of your fired cases (to get your chamber size) I can suggest a range to look at. I also need the length of the new bullet, since I don't have that information in my database, and what COL you are seating it to? To find water capacity, if you have Excel, go to my file repository and download the case water capacity file. It has instructions and a calculator built-in. The file runs in both Excel and the free Open Office suite spreadsheet program, Calc.

The IMR 4198 I suggested was before we knew what your gun was, and I really suggested it for shooting in a short barrel single-shot pistol, where your powder needs to put out early in the curve. It is a little quick for best performance in the rifle-length barrel. 37 grains will give you the same peak pressure as your 46 grain load of 748, but you will give up about 70 fps.

The 748 seems to be working for you with the Nosler, but it usually shines with the 168 and 175 grain match bullets. Ball powders are generally harder to get burning than stick powders, so they work best at near maximum pressure. Nonetheless, your starting load is not a bad guess at all. Even in a minimum chamber it will fill the case almost 90% and produce under 44,000 PSI. Keep in mind that every gun is a law into itself, though. and yours still may like the 748 just fine as you work it up? Reloader 10X came to mind because it was developed specifically for shooting lighter bullets, but when I run a table on 135 grain hunting bullet, it suggests IMR 3031, in a slightly compressed load, will produce more velocity at 55,000 PSI than any of the others we've mentioned. It may be the best burning rate compromise? If you are going to work up to higher pressures, though, you may have trouble fitting enough in the case.

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Hello,
I will be checking out that file repository just as soon as I get the new computer on line. Thanks again for all the feed back on my question, but I have finally talked Steve into staying with the 125 grain Nosler that we have had such good results with. Steve is a great shooting amigo, but he often gets too wrapped up in new goodies instead of staying with proven concepts. An example is his latest new toy, an F Class bi-pod for shooting at groundhogs! Instead of working with a great bi-pod that he already had, he is hoping to improve his shooting with another new toy. Basics are a must if one is going to shoot well at long range. The military taught me that back in 1964 and I haven't seen much to change my mind in all these years. I keep hoping that he will get a computer so he can ask his own questions so I can work on some questions of my own, like the last one that I sent in. :-)~

BTW, unclenick, thanks for the offer to use your site. Does it also have tables for establishing trajectory on a given load? Say the drop at 400 yards on that 125 Nosler with the load I stated I am using. According to my reloading manual the speed should be 3000 fps at the muzzle, and I am using the same barrel length, same Federal cases, and the Federal primers as well. It would be a great help to know exactly what that round is doing when it gets out there at 400 yds.

To the other gentleman who suggested that we call the Sierra about that new bullet, we did! They had NO suggestions as to what would even be a good starting point since they have not worked up tables for that new bullet as yet. This is what Steve was told when he called Sierra. It would seem that even Sierra goofs once in a while?

Thanks for the help,

longrangehunter