Latest activity
New .22 actions still coming?
- By Rob01
- All Things Rimfire
- 50 Replies
What the hell was I shooting in matches from 2017-2020 then? lol
Seriously though the straight contour barrels did start hitting around then and then started taking off around 2022 or so but plenty of PRS specific rifles in the early days. Here’s 2017 in a match.Not sure why everyone is so worried about prefits on a Rimfire though. Yes on a centerfire where you burn a barrel out in 2-3000 rounds but in a Rimfire where you will shoot over 100,000 rounds and spend over $20,000 in ammo to even be close to burning it out it’s not as big of a deal at least for me.
WTB Mk12 mod 1 upper
- By greg1147
- Buy - Sell - Trade
- 11 Replies
Good luck in your search, easier to build it
Maggie’s Motivational Pic Thread v2.0 - - New Rules - See Post #1
- By 168BTHPM
- The Bear Pit
- 295232 Replies
Lake Tahoe is nice this time of year.
6mm Creed AR10 Feeding
- By LRRPF52
- Semi-Automatic Rifles
- 3 Replies
The AR-10 was never designed around the 6mm with OTM meplats. What happens with the narrower neck is exactly what you’re experiencing.
The neck and projectile are able to present lower than the feed cone cut into the breech.
A very talented machinist, gunsmith, and engineer I know tackled this problem by cutting an extra set of extended feed ramps from the feed cone, without cutting into the feed cone depth (because this will jeopardize case web support under pressure during firing).
It’s very hard to get in there though without damaging the barrel extension or screwing up your breech.
______________________________________________________________________________________________
What I would try before doing any mods is get some Lancer 7.62x51 mags and seeing how they feed the 109s.
That will probably solve your problem since they are thinner lips, allowing higher cartridge presentation.
________________________________________________________________________________________________
You can also reach out to Seekins and ask if they have any recommendations.
Another thing to try would be to make a tool with a .308 case wrapped in 400 grit sandpaper. Install the tool in a hand drill.
Take your PMAG and spin the tool inside the feed lips to change the inside lip angle a bit higher, so the cartridge biases more upwards upon stripping from the magazine.
You can also add material to the back of your PMAG spines right as low as possible in the mag well location where there is contact, so it biases your magazine angle nose-up.
This is what Geissele did with their 6mm ARC, with the trigger guard nose. It protrudes into the mag well to bias the magazine so they don’t experience the same thing you are, as it is a problem with 6mm and certain projectiles, especially secant ogives with OTM meplats.
Let us know and we’ll help you along the way to get it sorted.
The neck and projectile are able to present lower than the feed cone cut into the breech.
A very talented machinist, gunsmith, and engineer I know tackled this problem by cutting an extra set of extended feed ramps from the feed cone, without cutting into the feed cone depth (because this will jeopardize case web support under pressure during firing).
It’s very hard to get in there though without damaging the barrel extension or screwing up your breech.
______________________________________________________________________________________________
What I would try before doing any mods is get some Lancer 7.62x51 mags and seeing how they feed the 109s.
That will probably solve your problem since they are thinner lips, allowing higher cartridge presentation.
________________________________________________________________________________________________
You can also reach out to Seekins and ask if they have any recommendations.
Another thing to try would be to make a tool with a .308 case wrapped in 400 grit sandpaper. Install the tool in a hand drill.
Take your PMAG and spin the tool inside the feed lips to change the inside lip angle a bit higher, so the cartridge biases more upwards upon stripping from the magazine.
You can also add material to the back of your PMAG spines right as low as possible in the mag well location where there is contact, so it biases your magazine angle nose-up.
This is what Geissele did with their 6mm ARC, with the trigger guard nose. It protrudes into the mag well to bias the magazine so they don’t experience the same thing you are, as it is a problem with 6mm and certain projectiles, especially secant ogives with OTM meplats.
Let us know and we’ll help you along the way to get it sorted.
