I have a Browning BARII in .270.

Have heard that some slower powders create high port pressures in the reloading system for this type of action ie. semi. and that its best to use a slightly faster powder for semi actions.

I want to use H4831SC and 130gn bullets. Nosler probably.

Any tips.

I have heard also , that very slow powders are not good for the action of semi-auto. If i remember correctly it was m1 grands and m14. More help is needed on this one question????

This precaution DOES apply to the M1 Garand, due to the possibility, however remote, of bending the operating rod. I am not sure about the M14/M1A, since it has a short, straight rod as opposed to the long, dogleg configuration of the M1's rod. It is also a good precaution on the Remington M740-M742 series, but I don't know if it applies to the BAR! I had a BAR in .308 Win., and of course, medium-burning powders work best in the small .308 case.

[ 11-01-2003, 18:54: Message edited by: eldeguello ]

I live in TX in USA and shoot a 308. I Use W748 and a 150gr bullett. My chrono vel. is about 2780 with a Hornady 150 SST. I can't tell you what to use in a 270 or 3006 as I don't either of them. My manuels tell me to use medium burning powders for semi-auto's. My rifle is an M1A. I would suggest trying to find out loading for the M1 Garand. Use it to start up. Sorry I can't help you on loading data for the Garand, should help in the Browning.

The safest advice would be to use something pretty close to what's in the factory loads, which the rifle's tuned for. George Frost's "Ammunition Making" book says that in the early 1960s when he was with Winchester-Western most centerfire rifle calibers were loaded with 4064. "Hatcher's Notebook" has a table of powders from the immediately post-WWII era listing 4064 as a powder to be used in Magnum capacity cartridges, so it was regarded as a slow one at the time. Bet that's what was in the original .270 factory loads, and that powders of the same general burning rate are used in the standard factory loads of today. He also listed 4320 as "for large capacity military and sporting rifle cartridges." It's pretty close to 4064 on most burn rate tables and loading manual data.

Here's a good M1 Garand target load: 47 grains of IM 4064, Sierra 168-grain HPBT Matchking, G.I. brass, FGed. 210 primers. You can substitute 165 grain hunting bullets for 168 grain Matchking. Very accurate in the M1's!!

Use a mid range powder for a BAR. Not the slowest, but not the fastest. Now, with that said, the only way I can get my 270Win 7400 to cycle correctly is to use 54gr of IMR4350 with 130gr bullet. I tried all the mid powders like 4064 and varget like the techs at Sierra said to do, and it wouldn't cycle right.

bigcountry.
I have used mainly H4350, 55gn behind a 130gn Nosler ballistic tip. Works fine, it was that this powder dosent fill the case 100%. But I guess that is another topic in itself.
Cheers