Home Forums Hunting & Shooting Competitive Shooting 308 Match Chamber Help...

I've purchased a 98 Mauser chambered in 308 Winchester. It has a match chamber so as you know standard factory ammo won't chamber. I've been told that you can get an old 45 ACP sizing die to modify to work as a small base die. Is that feasible, or should I just get a RCBS small base die? What other equipment will I need. Can you use collet dies? My only experience in reloading is strictly hunting ammunition.

I had a similar problem with a batch of
" once fired range pick up " brass I'd bought.
FL sized it all, trimmed, checked pockets, etc.
Loaded some up (50 ?) with a proven load.
Stuck the first one. Woops
I happened to have the bag that had a cleaning
rod with me that trip. It wasn't stuck too bad,
and came out pretty easy. The next one stuck
pretty bad, and I had to work to get it out.
Visually checked down the hole. Nothing.
I had some of my other loads with brass
I'd bought new. Functioned just fine as always.
Some of this "reconditioned " and "once fired "
brass people are selling is crap.
Be careful with what you buy

Are you trying to chamber an empty case or a loaded round?

I had tried to chamber a snap cap as I like to release the pressure on the firing pine spring while not in use. Since it isn't to specs it wouldn't chamber.
I'll try loaded factory rounds next.

Never mind…. If I’d pay attention to make sure all is aligned it wouldn’t be a problem…
Snap cap and loaded rounds all chamber.

Most rifles you can hold the trigger back as you close the bolt.

If i had a hunting rifle that wouldn't chamber factory ammo i would have it rechambered to something that would. I have a 308 Obermyer reamer which is just one of the myriad full bore chambers. It works great to to and including the 185 Juggernaut bullet. It works with 200 grain partitions also.

Standard reloading dies work for resizing

Yes. Don't know why guys don't know that.

I'd say your chamber is out of spec. I've got multiple match chambers including Obermeyer, M852, and a Fullbore. They all chamber factory ammo just fine.

There's only two situations that come to mind where an "in-spec" chamber might not chamber factory ammo;
1) If it's got a tight neck (primarily meant for benchrest where they're outside turning necks). I'd guess not likely on a Mauser rebarrel.
2) If it's got a short throat, then some longer seated factory rounds might not chamber because the bullet is jamming in the leade.

Snap Cap not chambering!!! I'd say you've got problems. It's not a 308 at that point.
If you have access to the smith who did the work, I'd ask him specifically what "308 Match" reamer he used. I forsee a clean-up reaming with a good smith and a known good reamer.

Try new brass, using xyz fired brass from who knows what is a schitt show from the get go.

you could try this sizer die


https://www.precisionreloading.com/cart.php#!l=FRS&i=018311




it works for me on a 308 with a tight chamber



if that doesnt work you need to run a finish reamer in that chamber

Web search "pound cast" method to determine your chamber neck and throat dimensions. Your match chamber may have a tight neck, requiring neck turning to allow fit. Try clambering a full length sized cartridge case.
Measure the of neck diameter. If it doesn't fit, even after full length resizing, or a small base die sizing die, if is likely the case neck needs thinning ( hand tools available. Easy to do.). Often a bench rest barrel will have the neck diameter stamped on the barrel.

Measure the O.D neck diameter of your factory of reloaded round (0.000"), then compare the measurement to the reading you get from the "pound cast" determination. You need the thin the necks enough to be a scootch smaller than the chamber neck.

You could have the neck opened up by a gunsmith to a "standard" neck diameter.

Sounds like you need a chamber cast to start. From the measurements taken off that you can figure out dies, seating depth, etc.

See above post….
All is good. The cartridges all feed very well….