Let me give you a little history which will hopefully help you help me
About 3 years ago I had R+D Precision do a semi custom rifle for me. At the time I couldn't afford a full custom so he trued the action, bedded it in a mcmillan and cut the barrel back a little bit and re-reamed the neck and shoulder. About a year ago GAP built me a full custom rig. I can't get it to shoot 1/2 MOA with match grade factory ammo so I'm working on some loads for it.
With that being said this morning I went to the range with a bunch of reloads that I'd put together hoping to get similar results to all the other guys on here with GAP's. After shooting some brand new Winchester Brass I then went to my once fired FGMM Brass. During the reloading process no matter how much I cranked the die down we could never get the shoulder to bump back. I'm using a Forster Co-Ax and Redding Type S bushing dies.
Using an RCBS Precision Mic I'm measuring the once fired casings, and they are about 0.004" under the zero mark which on the RCBS Precision Mic is Saami spec. So my shoulder are already 0.004" under Saami spec (This is a good thing).
Now the problem. I read on here and every other forum that as reloaders we should bump the shoulder back at least 0.001" to make sure the cases will ALWAYS chamber. During this process I mixed the GAP fired FGMM cases and the "factory" Remington chambered fired FGMM cases. So when I got to the range and went to shoot my groups for a ladder test there were rounds that wouldn't chamber. I've loaded up approximately 36 and half of them won't chamber. I'm assuming the ones that won't chamber are the ones that came from the Remington "factory" chamber (NO FAULT OF R+D).
Now in using the Co-Ax I've set the die down (full length die) as far as I feel comfortable with "break over" on the Co-Ax without damaging. Now after much measuring and comparing the problem is about the last 1/8" of the case just above the belt. So is it just match chambers that you won't be able to "bump" the shoulder and in so doing you won't be able to truly size all the way down the belt?
I'm sure some will comment that Larry Willis has the answer and this TRUE, but without his die is the answer just that my GAP cannot use once fired brass from a "factory" chamber (ie I can't buy once fired brass so any old joe blow internet)?
I've read and searched and I also don't understand "head spacing on magnums" either.
With that being said this morning I went to the range with a bunch of reloads that I'd put together hoping to get similar results to all the other guys on here with GAP's. After shooting some brand new Winchester Brass I then went to my once fired FGMM Brass. During the reloading process no matter how much I cranked the die down we could never get the shoulder to bump back. I'm using a Forster Co-Ax and Redding Type S bushing dies.
Using an RCBS Precision Mic I'm measuring the once fired casings, and they are about 0.004" under the zero mark which on the RCBS Precision Mic is Saami spec. So my shoulder are already 0.004" under Saami spec (This is a good thing).
Now the problem. I read on here and every other forum that as reloaders we should bump the shoulder back at least 0.001" to make sure the cases will ALWAYS chamber. During this process I mixed the GAP fired FGMM cases and the "factory" Remington chambered fired FGMM cases. So when I got to the range and went to shoot my groups for a ladder test there were rounds that wouldn't chamber. I've loaded up approximately 36 and half of them won't chamber. I'm assuming the ones that won't chamber are the ones that came from the Remington "factory" chamber (NO FAULT OF R+D).
Now in using the Co-Ax I've set the die down (full length die) as far as I feel comfortable with "break over" on the Co-Ax without damaging. Now after much measuring and comparing the problem is about the last 1/8" of the case just above the belt. So is it just match chambers that you won't be able to "bump" the shoulder and in so doing you won't be able to truly size all the way down the belt?
I'm sure some will comment that Larry Willis has the answer and this TRUE, but without his die is the answer just that my GAP cannot use once fired brass from a "factory" chamber (ie I can't buy once fired brass so any old joe blow internet)?
I've read and searched and I also don't understand "head spacing on magnums" either.
