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Discussion Starter · #1 ·
I have always used R15 and Varget ( I have plenty)for bolt guns in .308. In a few weeks, I plan on playing with this new to me 308 Garand. I am installing a Shuster Adjustable Gas Plug, and haver several brands of factory ammo to try out; Question, is R15 and or Varget comparable in pressure curves to IMR 4895?( I have none) I have some CCI #34 primers, just want the optimum powder for 150-168 gr bullets. How about Win #748 or BLC2? Any help appreciated.
 

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Discussion Starter · #2 ·
Well...forget I asked; I called and talked to several folks from Sinclair Int'l to a local gent our here who has 5 garands. They both suggested IMR 4895 as "best" and the local guy has it in stock. I'll just pick up a couple pounds and start there. They all said any of the CCI primers were really ahrd enough, but I have several hundered of the #34's. I could play around with the other powders, but what the hey, wish me luck!
 

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That's what I've been loading for my Garand forever... IMR4895 and the 147grn FMJ, and that is where I started with the .308/7.62mm for my M1a. I've fiddled with IMR3031 and IMR4064, but I haven't found any reason to give up on IMR4895.

Good luck and let us know how it goes!
 

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I'd stay away from anything slower than IMR 4064, but the guys are right - H4895 or IMR 4895 are about perfect. That tanker barrel should give you some earsplittenloudenboomer effect!
 

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Powders that work ideally in a given bolt action rifle might damage an M1.

Hmm, let's see...so this is a 308, and a tanker. That complicates things. First you might want to ask the guy who did the tanker modification what he recommends for ammo and powder, if you know who did the modification. I'm not sure that standard M1 Garand advice can transfer 1 for 1, here. The barrel length is different so the gas port is going to be a lot closer to the chamber, here (the gas port on a standard M1 is quite close to the muzzle). He might have also played around with the gas port size. All of this could affect function, and how much pressure the gas piston "sees."

But without intimate knowledge of what was done, for the powder not too fast, not too slow is likely still good advice. But drilling down...if you look at M2 Ball, the .30-06 ammo that the M1 Garand was finally designed around, yeah, sure, IMR4895 is the ticket for reproducing M2 Ball loads, with IMR4064 being the sure ticket if using heavier match bullet loads (such as for the Sierra Matchkings).

On the other hand if you look at M80 Ball loads for the 7.62X51NATO, the powder it was designed around was WC846:

http://www.scribd.com/doc/13776288/TM-43000127#outer_page_194

The commercial equivalent of this is BL-C(2). If you look at a burn rate chart:

http://www.hodgdon.com/burn-rate.html

Your Varget or R15 actually look like they might be better choices than IMR4895 if the gunsmith who modified this M1 designed the thing around M80 ammo, particularly if you start using the heavier 168gr bullets that you mentioned. If your powder is too fast for the bullet weight, you can start putting some improper bends in that op rod pretty easily (the op-rod is supposed to be bent in a very specific way), and your accuracy will go to pot, and you'll have to get the op-rod rebent to spec to get it working right again. The adjustable gas plug will give you a little wiggle room, though. Just follow the installation instructions...turn it all the way down such that the action doesn't cycle, then gradually turn it up until you have reliable cycling with your ammo of choice, and no more.

All that said, it isn't completely inconceivable that your rifle could love IMR4895 charged handloads.

Hard to say for sure what the gunsmith in question did to this rifle, though. There are a number of folks that do this mod. Hopefully it was one of the more skilled outfits that did it such as DGR, instead of a chop-job in Bubba's shed out back. An improperly setup and fed gas operated rifle is nothing to play around with...not worth risking getting maimed or killed over. Incidentally I wouldn't mess with a .308 M1 Garand, myself. Well, at least one that didn't have a carefully calculated reduction in the mainspring spring rate. It's a long-action autoloader...giving the bolt free time to accelerate the cartridge beyond what it was designed for by running short action cartridges through it without modification is just asking for troubles with slamfires and such.

You may or may not take what I say with a grain of salt. I'm certifiable OCD about firearm safety and keeping my boyish good looks, and loathe the idea of living with unnecessary design compromises or shortcomings in my firearms when I don't have to.
 

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Oh, one more word of caution here...if you get that gas system going too fast you will have extraction problems, too. The M1 is sort of extreme in the way it extracts even in its original form. With its timing it actually starts yanking on the case head before the case has cooled and contracted from gripping the chamber walls. This is why you get a lot of case lengthening and reduced case life in reloading for the rifle (usually 4 reloads before you gotta toss the case)...because the extractor is yanking on the case at a point where the case is both softer from heat and immobile from holding onto the chamber. It's not too hard to imagine that if you start pulling harder that you'll start ripping off case heads and such, which is not a good thing.

Also it isn't just the burn rate you have to consider, but the curve itself vs. the projectile weight vs. the gas port distance from the chamber. It's not always a simple matter of looking at burn rate charts, so maybe I should moderate what I said about Re15 or Varget sounding reasonable. With gas operated rifles likes these, taking the most conservative approach possible is always the best idea. If you know something works best, best not to stray too far. Sometimes pressures change with a different cartridge design, as we have with the .30-06 vs. the .308. If you want to balance these all out as a firearms designer you must consider all of these things if you don't want to use a bandaid solution such as the adjustable gas port, which the M1 did not originally include. Once you know all those things you can get an idea of how much gas the port sees as a given cartridge is fired. Hence the genius of folks like John C. Garand.

I guess what I would do if I couldn't contact the maker of this rifle, and I was set on keeping it, would be to start by testing out some milsurp M80 with the adjustable gas plug, and see how it does. Maybe work your way up with the gas plug to where you're comfortable with function and reliability, and see how far it tosses the brass. Then move back to the stock gas plug, and compare to see how far it is flinging the brass. If it is significantly farther than you found in the adjustable case, you may have a problem.
 

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Discussion Starter · #8 ·
Thanks guys, all good stuff! I do plan on setting it up with m80 surplus/Winchester commercial hardball first. My reloading will be mostly for hunting(deer coyotes,etc), so I may just stick to a 150 fb. I'll report later.
 

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I reload for my Socom16, which has a 16" barrel with a standard length gas piston/op rod. It is true the timing may be a bit tricky, the Socom has a bigger gas port to compensate for the shorter barrel. I would hope whomever did the conversion is familiar with the necessary port size for a shorter barrel of a Tanker, but you may be able to find some of that information elsewhere on the internet (taken with the appropriate grain of cautionary salt!)

Thankfully, you chose .308, and, like Miatakix mentioned, your case cycles should be limited to 4 or 5 loadings... .308 brass is a little cheaper and much easier to find than .30-06.

Federal makes some M1a specific ammo, 168grn OTM ('Open Tip Match' or hollow points... ;D ) so if you are looking for a standard for the 168grn bullet, this would probably be your best choice. In the 147grn bullet, any quality surplus or commercial production ammo would provide this. I always take a box of factory with me when I'm testing handloads, to compare action behavior and to provide consistent chrono readings and accuracy.
 

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IMR does stand for Improved Military Rifle.

Ball L C # 2 is a military lot number.


W748 would work well.
 

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Discussion Starter · #12 ·
I'm really leaning toward the 165-168 grain bullets for my purposes. I have found some good recipes with IMR 4895 ( just p/u a can today) but does anyone have a good recipe w/BLC2 or the W748 ( I have both those powders.) As far as 150's go, all my hardball is either 147 M80 or W150 fmj. I have a few boxes of Federal Blue Box factory 150's to use for hunting/coyotes.
I have Nosler 168BT and Barnes 168TSX on hand for reloads ( Iuse these in my '06) I was thinking the Nosler might be better to start with?
 

· El Kabong
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The M1s were designed to operate with a 150ish grain bullet.
I would never use anything over 155 in mine. You also have to consider the 2700fps limit.
You will have to watch your pressure like a hawk
 

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Nothing wrong with using the 165-168gr range of bullets in the M1. They are more accurate out of my HRA M1 than the 150s, in general. A Sierra Matchking of about that weight with some IMR4064 pushing it is a proven .30-06 match load. But, again, this isn't your run of the mill M1, it's an entirely different animal. If it were me trying it out of that .308 I'd probably try the BL-C(2), first, but I can't say for sure, I don't have any experience with .308.

With the shorter barrel I actually like the idea of the lighter ~147gr bullets better. Lets you use a faster burning powder such that you don't have as much unburned powder (read: muzzle flash/blast).

So I guess you weren't able to figure out who did the conversion, preacher?
 

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Discussion Starter · #15 ·
No sir, the guy I bought it from didn't know who did the conversion. It is first rate work,though, not cobbled together. He said it was very accurate with the Winchester Commercial hardball factory loads. As far as it being loud, heck, I have already loast all my high frequency hearing, nothing seems very loud to me anymore,ha.
I think I'll get me some 150's to start load work with, either Speer or Sierra and that way I don't have to play with the adjustable plug very much, once it's set. Will report later, thanks again guys.
 

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I have been building some loads for my Socom16 using 3 different powders (IMR's 3031, 4895 & 4064) with the 168grn Nosler bullet. Accuracy is better than the M80 surplus and my handloads using 147grn bullets (Winchester, Prvi, Hornady.) Because I'm still in development phase, I don't have any concrete loads yet.

My standard M80 equivalent load is 43.5grn IMR4895 under a 145grn Prvi FMJ in a LC or PMJ case and the #34 primer. This is my load for my rifle, I started at 40grns and worked up.

The IMR3031 and the 168grn bullet was an experiment using faster powder with a heavier bullet in the short barrel. The jury is still out on that and I would NOT try that in your M1; sticking with IMR's 4064 and 4895 and the 168grn bullet. I do not have any experience with BL-C(2) or W748.

Just FYI, the Hornady 150grn bullet is for the M1/.30-06, the cannelure is further forward for proper seating in the .30-06. I have 1000 of them I'd bought for the Socom, but once I found out about the cannelure, I just saved them for the Garand.

The Hornady is on the right...

 
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