Discussion in 'Handloading and Reloading' started by JonSmith, Feb 22, 2008.
Without the port buffer, the brass takes a beating on the scope mount and on the rear of the ejection port.
I don't immediately recollect my H4895 load, which the rifle likes best, but using a good 168 grain match bullet, CCI standard large rifle primers, and the aforementioned RA military brass, 43 grains of Varget makes a great middling load that is more accurate than I can shoot the rifle. No pressure signs.
Even better, since I got one of the early "tight chamber" rifles which are cursed by many, but which I love since I handload for it anyways, I get ZERO case stretching, and the force required to resize this brass in a RCBS standard base, X-die, is virtually imperceptible. I can reload the same case and fire it repeatedly with no stretching, using the moderate load I offered above.
I did talk to the factory customer service guy too.
My rifle shot 150 gr Australian ball well. It took grinding the bottom of the turret to get the elevation zero'd at 100 yards. My reloads were with 168 SMK and 174 GI FMJBT. They shot high, like 4" at 100 yards. And they kicked more.
So, when I do get enough empty brass, I am going to load 150 grain bullets.
Based on the type of action I think you want to use a medium to fast burning powder. Anything in the 4895 burn rate should do very well. That is H4895, IMR 4895, and AA2495. Having used IMR 3031, that should work well. I would be curious to try AA2520, a ball powder, and that is an excellent M1a powder.
I would be concerned with Varget. Though the load of 43 grains Varget with a 150 should be a low pressure load, Varget is a very progressive powder. In the one M1a I tested with Varget, 43 grs Varget with a 168 SMK caused case head separations. That tells me that the residual breech pressure is high at unlock. For a roller bolt action, I would rather use a faster powder that gives a quick kick and have the barrel pressure drop fast.
Burn rate chart.
H4895 is 72, Varget is 80 on this scale, AA2520 is 81. Varget is a rough equivalent of 4064, an appropriate powder for M1 Garand, and just fine in the roller locker.
Generally a case head separation is caused not so much by over pressure so much as it is by poor headspace. Even proper pressure for a cartridge which has had the shoulder set back too much, or exhibiting incipient case head separation, will lead to separation.
All this said, I agree that H4895 is a great powder in this application. Some get better accuracy with the Varget. As I recall 41.5 grains of H4895 and 168 SMK is the standard cross the course load in military brass. This combination will give good accuracy in almost any rifle.
Usually outrageously expensive.
Not commonly available
Sometimes one turns up second-hand on Gunbroker or Sturmgewehr.
Vendors like RobertRTG or HK Specialist have one or two once in a rare while.
Metal clippy thing with rubber insert bouncy-thing.
stubbicatt & W.E.G. : I have been trying to get a port buffer forever, any thoughts on where to get one? Also, what would be a fair price?
I usually use Lake City cases. I have reloaded some of them more than six times w/o problems. The flutes are ~usually~ just cosmetic. I've found that some military surplus loads extrude brass into the stripes. I've had some hand-loads do that too. It's pretty obvious when it happens. I scrap the brass and mark the load in my book as unsuitable.
W.E.G.s exactly right, the port recoil buffer has made a huge difference. Before getting one, lots of my brass was dented badly enough that I scrapped it. (It reduced the throw distance of the cases from 50' or so to 15-20' so I can find most of it too!)
Because the action is delayed recoil operated, I've found that it is remarkably un-finicky with respect to bullets and powders. I've used jacketed bullets from 100 grain Plinkers (R) to 180 gr BTSPs. I've had the best results with 150 FMJ and especially 168 gr. BTHP bullets.
The powders that have worked best for me are IMR 4895, IMR 3031 and WW 748. WW 748 is my go-to powder. I've used it with pretty much every bullet. It is great with 150 gr FMJBT bullets. I usually use loads in the lower end or middle of the range in the load manual. I figure that as long as the action cycles, and the bullet goes where I point, that is all the power I need.
I prefer WW large rifle primers because they feed better than CCI in my progressive press. Neither seems to make a difference in the way the ammo shoots in my experience. It may be that a better shooter than me might have noticed differences that I didn't. YMMV.
Lymans 311291 cast from Linotype with a gas check and Alox lube over WW 748 function perfectly w/o leading, for me.
me and a buddy are reloading for our beastly ptr 91's and they do eat brass! i might have found a guy who produces refabs of the ptr port buffers. i'll let yall know when i get more info!
You can make one like I did. Its not pretty, but it works.
I just got an adhesive "furniture pad" from Wal-Mart. Noted where the brass was hitting the receiver (aft of the ejection port.) Cut a piece of pad, and stuck it on. Vastly reduces neck damage.
Actually doesn't look too bad. Its black, and matches the gun's finish pretty well.
How about a picture of your handiwork? How long before you have to put another one on? Neck damage seems to be my biggest problem.
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