Recently got a gun from a guy on the hide. 300 win mag. Recently got 200 brass of fgmm once fired. I fired some factory loaded fgmm from my rifle. Headspace from fire formed brass from my gun measures 3.306 with Sinclair comparator. Headspace from once fired brass is 3.321. I used my rcbs full length sizing die and rcbs shell holder and the smallest I can get my brass down to is 3.318 even cranking die down for a hard camover. What would everyone advise? Should I try Redding dies, should I shave my shellholder down about .013 with sandpaper, even if I get the Redding competition shellholders that will only get me .010. Any help would be greatly appreciated. Thanks.
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Resizing once fired brass from a different gun to fit into a match chamber
- Thread starter ForeverZ01
- Start date
My gun is a full custom gun with a bartlein barrel chambered by Texas brigade armory. It chambered the factory rounds with no problem.
There really isn't much you can for this without wrecking the brass. I would almost be also that the web area (base) is larger, which only a small-base die would cure (Larry Willis makes a die for this) - but at the penalty of weakening that area somewhat.
General rule: New rifle, new chamber, new brass. Your situation is not that uncommon.
EDIT: Remember also that the competition shellholders are marked with the amount that they decrease headspace. You get the most bump with the "standard" shellholder.
General rule: New rifle, new chamber, new brass. Your situation is not that uncommon.
EDIT: Remember also that the competition shellholders are marked with the amount that they decrease headspace. You get the most bump with the "standard" shellholder.
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Ok if I do buy new brass, say Norma brass, and shoot it and want to bump my shoulder back .002 after once firing it, how would I do it if my die isn't able to reach that headspace.
You have to take a few thousandths off the resizing die.
I had the same problem when I re barreled a 7 mag.
I could not bump shoulder back enough with the new head space.
I gave my smith some fire formed brass and my dies.
He took it from there and works perfect now.
Sent from my iPhone using Tapatalk
I had the same problem when I re barreled a 7 mag.
I could not bump shoulder back enough with the new head space.
I gave my smith some fire formed brass and my dies.
He took it from there and works perfect now.
Sent from my iPhone using Tapatalk
If you shoot the new brass in the new gun you shouldn't have a problem. As AIAW said, it's not an uncommon problem with used brass from another firearm. As an aside, beware of the so called "once fired" brass. Frankly, there's no way to actually confirm (unless it's from someone you know personally & trust) that so called "once fired" is indeed that. If it's from a commercial source it could have been fired several times through different firearms. Granted, that's worse case scenario but personally I would never trust that kind of brass. Trust me, I work at a range, you wouldn't believe where some of the range brass ends up after purchased by unscrupulous individuals.
Do Redding dies typically have a tighter headspace than rcbs, because this isn't the first trouble I've had this problem with rcbs dies. I considered getting a different die cause this one works fine for my other rifle. Considered having a die for each.
No, they are generally all cut to either SAAMI or CIP spec. Without knowing which particular reamer was used for your chamber, your only option is to have a die made off of a once-fired piece of brass fired from the chamber you'd like a die made for.
Ideally a die would be cut using the exact reamer spec as they do vary of course.
What you have is a nice tight chamber (not a bad thing) - but you have some sloppy once (or multiple as Fursniper mentioned) brass.
Believe me - ditch that once fired stuff and start from scratch with some nice new Norma, Nosler, etc. brass. It will save you a ton of pain and anguish.
Ideally a die would be cut using the exact reamer spec as they do vary of course.
What you have is a nice tight chamber (not a bad thing) - but you have some sloppy once (or multiple as Fursniper mentioned) brass.
Believe me - ditch that once fired stuff and start from scratch with some nice new Norma, Nosler, etc. brass. It will save you a ton of pain and anguish.
Fursniper are you saying that my current dies could resize different brass to a smaller size? I took some fire formed brass from my gun and tried to resize it to bump the shoulder back .002 and after putting it through my die it actually grew by .004. This brass was factory fgmm 190 grn that I shot so I know it's true once fired.
What I'm saying based on my experience is if you start with new brass with a new (different ) gun, after you fire it, you should be able to resize it back with a two thousandths shoulder bump and be good to go. Based on several decades of reloading with many custom and factory rifles that is my experience. Having said that though, belted cases have some unique challenges of their own sometimes.
I had a similiar experience as you with brass once when I rebarreled a 308 rifle. After resizing with my usual bushing die, I just could not get the brass from the old barrel to work in the new one, just couldn't get the headspace right. So I tried running it all through a standard 308 body die. It was an improvement but still not right. Took the body die to my gunsmith & had him mill off just a "sliver" off the bottom of the die (I think it was about .003, it was quite awhile back) and tried it again. Wa-la, the old brass chambered quite nicely in the new barrel, shot it and after resizing & triming after that I got quite a few reloads from that brass after that. It was all my own brass & lapua brand so it was worth a little extra effort. You might try this if you really want to try and salvage your "old" once fired stuff. But my experience was with non-belted cases, your cases my be demonstrating some of the associated problems with belted cases with the dreaded "bulge" just ahead of the belt than can be difficult to get out with a standard die sometimes. (I really don't like belted cases!) There is a special die that is made for belted cases that solves that problem though. Sorry, I can't recall the source for it but maybe someone can jump in with what it is and where you could buy it.
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I mentioned one of them above: http://www.larrywillis.com/windex.html
It works, just rather tedious!
It works, just rather tedious!
If you've preloaded the press enough that that it's not springing open when it cams over, and brass resized through it is coming out .012" too long, there's no way that your current die is going to get the brass to a headspace that will fit that chamber.
You will either have to machine the difference off the shellholder or the die to get the brass shorter than the minimum it can form now.
I recently chambered a 6.5 CM barrel for my AIAX. A Redding die could not bump the shoulder on brass fired in that chamber. I had to machine a few thousandths off the end off the die to be able to bump the shoulder.
I had the same issue in 6.5 Creedmoor between barrels on my AI. My forster die couldn't bump down far enough (I ended up sending this to forster and they took off material off the bottom of the die (you can actually do this yourself b/c it's not like it will affect concentricity that much (that's your press). The next problem I had was the web area was stretched out to fit the original barrel so I couldn't even chamber the piece of brass without the web area getting totally scuffed and it was a big issue. I used a small base die (typically used for AR platform rifles). On both of these prior issues though you will overwork the crap out of your brass. I highly suggest annealing especially if you try to bump the shoulder back more than 0.008. You will cause a casehead separation. Lots of info on the web about this last part. I ended up checking for this with a paperclip on the interior of my brass. Luckily I did b/c overnight some of the piece of brass cracked by themselves (it was very weird). I ended up sifting and tossing out 20% of my brass after bumping my shoulders 0.009-0.010 back WITHOUT annealing b/c I can feel the ridge where the casehead will separate with the paperclip.
I tried a Redding die and it was capable of sizing about .004 smaller than my rcbs die. This is still about .008 shy of getting it bumped back .002. I spoke with the guns builder and he asked me to send it back to him with brass and he will cut the chamber to match my sized brass. Great guy.
Get yourself a Forster FL sizing die and send them the die with brass from your gun. They will adjust the die free of charge so it bumps shoulders back to your desired headspace. I did this with a custom 6.5cm. We are talking $36.99 for a Forster FL sizing die and produces some of the least runout of any die with its high expander ball.
Gun is already on the way to the smith. The chamber was larger than I wanted it at the base as well. Brass would swell 15 thou above the belt.
