Differences in case capacity

[319]

I noticed my FC .308 cases don't hold as much powder as the R-P cases. These are all sized in the same RCBS SB die, and trimmed to the same length. I am using a "max" load of Varget(according to Hornady 45.0gr). The R-P case held all the powder just below the Neck/Shoulder junction. The FC cases held all the powder, but it was up into the neck, and made seating more difficult. Is this going to give me pressure problems? I don't think I would be worried much if I didn't have to turn my seating die down another couple thousanths to get the 155 Amaxs to seat to the same length as in the R-P cases. I also wouldn't be too worried if this wasn't a "max" charge. I have fired this exact load with no pressure problems in the R-P brass, but have not used the FC cases for this load. Any one care to jump in and tell me if I will have any problems with these?

[earl39]

I would rework the load as this could cause pressure problems.

Gary

[gotcha]

Federal brass is known to be a bit thicker/heavier than the RP &, generally speaking, the RP thicker than Win. I would go with Gary's advice.

[ShaneG.]

I had a load I used in RP cases in my 308,loaded same thing in some Prvi brass and took the primer out on a few and had sticky bolt lift. As said I would back off and work back up.

[bigedp51]

Separate your loads, example, shoot 150 grain bullets from Remington cases and 168 grain from Winchester cases. Do not mix cases or brands of cases for the same load, below is something that dates me but its a Powley Pocket Computer. Accuracy shooting is done by measuring case volume and NOT by case weight.

DO NOT MIX YOUR CASES FOR THE SAME LOAD. (internal volume controls pressure, consistent pressure controls accuracy)

Please note below for this computers calculations you needed the internal case capacity in grains of water to figure your powder charge weight.

[img width=600 height=257]http://i122.photobucket.com/albums/o254/bigedp51/powley-3.jpg[/img]

Just look at the variances below with the same batch of .308 Lapua cases at Acurateshooter.com
, and these are the big boys playing with their brass.

http://forum.accurateshooter.com/ind...3740238.0.html

[319]

Thanks for the info every one!