Need load help......

[Powderman]

How do! I need a practice load that will duplicate the ballistics of the Federal GM Match 168 grain load, in .308.

I intend to use MatchKings, and have a supply of Federal GM Match brass, unfired.

So, what do you recommend to get me to the 2600 fps mark? I'm especially interested in loads with ball-type powder; but something using IMR 4895 or 4064 or Varget will be interesting as well.

The rifle is an M1A NM, and I'm looking for good accuracy to 200 yards.

Any and all help is appreciated. Thanks!

[Smokey Joe]

Your request is easy...ANY of the powders listed in Lyman's 48th ed. will get you in the 2600's or 2700's fps. with a 168 grain bullet. These are max loads, though, and you should do the usual workup, starting at least 10% down.

You can find the same thing, I'm sure, in any published reloading manual. Which leads me to think...You DO use a manual, do you not??? Not just some load that someone put on the I'net???

And since you want a specific fps, and you're a serious target shooter, you do have a chronograph??? Because the velocities in the manual are what the authors got from THEIR gun, and your results will vary from that, as they will from anyone else's results with any other gun but yours.

Please, sir, if you don't have a published loading manual get one or more, and USE THEM. The PhD's in white coats that established those maxima do know what they're doing. And they can save you from having to re-invent the wheel, and Ka-Booming your precious Old Betsy in the process. And any yahoo can put any old thing out on the Internet--that doesn't make it safe.

Forgive me if I misinterpreted your post. Your question isn't one that someone who has the standard reference books to hand would usually ask.

[30Cal]

Fed GM is a duplicate of M852. The standard M852 duplicate is 41.5grs IMR 4895 in a surplus case. It may take a little more than 41.5grs to get 2600fps in a commercial case.

Ty

[Powderman]

Smokey Joe, thanks for the advice. Let me explain a bit...

I have been designated by my Chief as one of the Department's precision rifle guys. (We have two)

I was plinking with my M1A, and I have good luck with 43.0 IMR 4895, and mil surp 147 gr. FMJBT.

However, our issue ammunition is going to be the Federal GM Match ammo.

I can not afford $22-25 per box to practice. Thus, my best bet is to duplicate the factory load.

Ideally, I should break out the chrono, take some rounds to the range from the same lot, and start from there. But, time is at a premium, and I needed a starting point. Thanks for the advice, though!

And, yes--I have three Speer manuals, Nosler #4, three NRA books, and scores of stuff from the powder manufacturers--plus what I've tested out over the past few years. Nothing, though, on the Federal GM Match round.

[Smokey Joe]

Powderman--Thx for explaining! That eases my mind considerably! Looks like 30Cal has you covered for a load. Hope it works well for you. I'm not big into .308 myself.

Yr Dept. doesn't issue you practice ammo of the same quality as your duty ammo?? And they expect you to be a precision rifleman?? Sounds like the politicians are in charge once again. "Yes,but, whine, whine, well, you know, the budget, the voters, taxes, whine, whine." Sigh. BTDT; my sympathies.

[Powderman]

No problems, Smokey.

Of course they issue practice ammunition--but, take a small department (30 officers) and ammunition that costs 20 bucks per 20 rounds (wholesale price) and you see where I am right now.

[Unclenick]

Smokey Joe has a good point. You can work up loads with identical velocities with no problem (though you should get at least one box of the Federal to compare with what you work up over your chronograph; some are more accurate than others, so you want to match readings on THAT chronograph if you can do so without seeing pressure signs with your test powder).

I like Varget in .308. IMR4895 and H4895 require enough powder to increase the pressure almost 10% to achieve the same 2600 fps from a 22 inch barrel. In a Federal case (55 gr. water capacity level with the case mouth) using a Federal 210M primer, 42.7 grains of Varget comes out about right in my M1-A, but you should start at 40 grains and work your way up, checking for pressure signs. In the immensely strong Garand-style action, you are unlikely to run into trouble, but watch for primers getting too flat.

I've also had good luck shooting the 168 grain Sierra MK with 43.5 grains of AA2520 in that gun. But ball powders are harder to light up, and I discovered I had to use the bench rest shooter's trick of deburring the flash holes in my cases to get best accuracy. It brought 100 yard, slow-fire prone groups down from 1.5" in 0.75" firing 2520. Deburring flash holes did nothing for the more easily ignited stick powders. You can get a deburring tool from Sinclair.

I went through Gunsite's PR1 class with a tac rifle PMC .308 match loaded with the 168 grain Sierra MK. It’s a good approximation of the Federal product. It worked fine, except on a popper 748 yards out across a valley with a strong cross-wind. Nobody shooting the 168's could hit it consistently. Two years later I found out why.

It was the first time I attended the Long Range Firing School held every year at the end of the National Matches at Camp Perry. I and numerous other cursing people had come loaded with the Sierra 168's, and from short range (800 yards is short range at that school) got a lot of complete misses. Guys in the pits reported back numerous keyholes among the shots that stayed on the paper.

It turns out that when the 168 drops sub-sonic (about 700 yards for match ammo) it gets very unstable. Sierra’s Chief Ballistician, Kevin Thomas also happened to be attending the LRF school that year and said the 168’s had been designed for 300 meter international competition originally, and that it turned out they work well at 600 yards for Service Rifle matches was a happy bonus for Sierra. Their newer 175 grain MK, however, is designed for longer range ballistics and doesn't exhibit this behavior. The next year I went back to the school with the 175's loaded and shot a 99 on the first 800 yard target. No problem there or at 1000 yards (shooter errors not withstanding).

The lesson is, if you go out beyond 700 yards, change to the newer bullet or don't take the shot. That may never be a consideration for you, but I thought I would toss the heads-up out there just in case.

Nick

[sundog]

Powderman, go to the Accurate web site for load data for 2230. Then check out Powder Valley for 2230-C ($65/8#). That's alot of shooting at $8 a pound for powder, and it works fine at 200. In fact, it works well enough I bought a few more. Also works in M1 Garand okay, too. Those store bought cannister powders are good, but when I can save this kind of money and it works, I do it. btw, testing in .32 Win Spl has shown this to be a very close match to surp WC844. A little dinking around with a chrono and you'll get a load that will work. sundog

[Unclenick]

Sundog,

I'd be interested to hear how your 2230 groups compare with 4895 or other standards through the same gun? Accurate Arms used to brag that 2520 was referred to as "Camp Perry powder". I haven't ever heard that at Camp Perry, but that's what their sales staff claims. My internal ballistics program has 2 grains less 2230 producing about the same chamber pressure as my 43.5 grain 2520 load. The summary is below:

Case, Fed .308, 55 gr. H2O cap., Fed. 210M primer, Sierra 168 gr. MatchKing seated to 2.800" O.A.L., 22" Bbl. Length.

AA2520
•43.5 gr. Charge Weight
•92.8% case Capacity Filled
•99.77% Burned in Barrel
•32.9% Balistic Efficiency
•51,849 PSI Peak Chamber Pressure
•7822 PSI Muzzle Pressure
•2604 FPS Muzzle Velocity

AA2230
•41.5 gr. Charge Weight
•88.5% case Capacity Filled
•99.42% Burned in Barrel
•33.1% Balistic Efficiency
•52,192 PSI Peak Chamber Pressure
•7435 PSI Muzzle Pressure
•2555 FPS Muzzle Velocity

You can increase the 2230 load about 0.8 grains and get to 2600 fps. This raises the peak chamber pressure about 3200 PSI, but that is still within SAMMI limits (this is PSI from a piezo-electric transducer, not CUP from a copper crusher, which gives a lower number in this cartridge), and only slightly greater than that produced by the Varget load I mentioned in my previous post. The 7520 PSI muzzle pressure is still below what the 2520 produces, which may help accuracy slightly with some bullets.

Anyway, how the groups compare is what I am curious to know, since I've never tried 2230?

Thanks,
Nick