And now for something REALLY completely different

[stagpanther]

I’ll have a go at it . .30 carbine I always wondered about an AR in that caliber.

LOL--I would much sooner track down an M1 carbine (ALMOST bought one at a lgs a while ago but the previous owner had done a bit too much modernizing for my tastes).

[CarJunkieLS1]

M1 Carbine in a AR-15...thats a 300blk loaded with 110 grain Round Nose made for a 30 carbine.

[FrankenMauser]

.357 Sig has been scratching at the back of my brain for this, since the beginning. But that seems too "common" for something 'really completely different'.

.400 Corbon, though... That's unpopular enough that it might fit.

[stagpanther]

Since I already have a Glock chambered to 9x25 Dillon the 357 sig has no appeal to me.

[smee78]

Looks cool, how about a 10mm Magnum?

[stagpanther]

I've thought about that--but what does it bring to the table that a 41 mag doesn't? Either way I would need a custom bolt probably.

[brasscollector]

50GI?

[stagpanther]

someone already guessed that--and the answer is no, I'm not willing to go that far out on the bleeding edge. : )

[brasscollector]

I'll take another stab at it...
22TCM?

[stagpanther]

That looks very interesting--but I'm already committed to something in large frame.

[9x19]

Has to be the slowest reveal in TFL history...

[stagpanther]

Has to be the slowest reveal in TFL history...
__________________
Make mine lean, mean, and 9x19!

And the most disappointing. My original negotiations broke down mostly due to lack of knowledge on making a PCC. I then switched to plan "B" and settled for-- as some of you had guessed-- a 9 x 25 Dillon barrel and bolt made by RMWXtreme. That however looks like it may take a very long time before it's completed, so in the meantime I started testing some loads based on a simple 10mm blow-back set-up.

The Circle 10 receivers with Odin stock set-up is very efficient in handling the recoil and bolt thrust of higher power loads even with a heavy bolt carrier. The Glock magazine remains a PITA with certain bullets when "swatted" into the chamber. I wish to the Gods that Colt made a magwell adaptor for large frame cartridges like their 9mm one.

[9x19]

Bummer...but wish you luck with the 9x25 moving forward.

[stagpanther]

Gonna be a long wait on 9 x 25 dillon--but eventually will look forward to seeing what it can do--shouldn't be too hard getting lighter bullets to go very, very fast.

[9x19]

Which mags do you use in your Glock for the 9x25, the 10mm?

No feeding issues?

[stagpanther]

Which mags do you use in your Glock for the 9x25, the 10mm?

No feeding issues?

I use standard Glock 10mm mags (though I don't especially like their design--a far better one IMO would be Colt's 9mm scheme enlarged to handle the 10mm/45acp/40SW etc) The only chokes I've had in my Glock 9x25 have been due to operator error--if I relax my grip enough that can cause a FTFeed--but as long as I hold it hard and steady and use a strong enough charge it operates reliably with a wide variety of bullets. I drop test every cartridge I load into the barrel prior to use. The Lone Wolf barrel I bought years ago was perfectly made, very sad they won't make them anymore. I configured mine to handle "full house" loads--and it does it with aplomb.

The 10mm case, like the smaller 9mm, in my experience is prone to widening at the base and weakening at the web after repeated loading. My personal theory is that the Dillon, by virtue of having a bit of shoulder, resists these stresses better over repeated reloads--I generally don't get many reloads of powerful "straight up" 10mm or 9mm cartridges before they expand too much at the base and are prone to splitting the case at the web.

[brasscollector]

What was the original idea, 44 automag?

[stagpanther]

Similar-- a 45 super +P.

I just got back from another session of "working out the bugs" with this build. I was experiencing a fairly high number of cases splitting and getting stuck in the chamber; even with relatively low power loads. I've got a fair amount of experience with blowback AR's in 10mm using Glock magazines--the blown cases are generally not the direct result of an overpowered cartridge; rather the angle of the feed from the Glock magazine often causes the BCG to slam the cartridge with quite a bit of force into the wall of the chamber doing one of two things, sometimes both. 1) it can easily set the bullet back in the case, which can cause a pressure spike; and 2) it stresses the case unnaturally sideways, giving the case a propensity to split at the web.



I had always "blamed" this problem on the high pitch angle of the cartridge as presented by the Glock magazine but I just happened to have a spare new nitrided KAW valley 10mm/40S&W BCG on hand and decided to swap it out with my older BCG, was surprised to see that there was an entirely different construction, the newer one resembles more closely a conventional 9mm carrier--but the "dummy gas key" has been moved significantly forward, as well as using a conventional AR style extractor as compared to the older 10mm BCG. Upon switching to the newer BCG the rifle fired and cycled without a hitch.

The circle 10 lower came assembled, but apparently came with a conventional strength bolt catch--in a blowback 10mm this will eventually fail, and mine blew apart today on about the 10th round down the tube. I replaced it with a seekins enhanced bolt catch--I would prefer to use a titanium one but those are basically "unobtainium."

PS-- I've actually found a few--but they are generally around $100 a pop!

[stagpanther]

Today I ran Hornady 180 gr xtp's using their max load of 14.9 grs. of Accurate 9, about as good as it gets for a 10mm cartridge in terms of velocity/energy. It clocked 1700 fps @ 1150 ftlbs at the muzzle and an SD of around 9 fps for 5 shots. my groups weren't especially good, around 2 MOA at 100, but it was very windy today--might get better results second time around. Being a blowback it makes a mess of the inside of the upper.

[stagpanther]

Tried the same load again today, less wind and true to my classic style, I managed to shoot a flier wide with each group.





Ordered some 180 gr golden sabres and Winchester HP's to see if they shoot any better than the xtp's

[jetinteriorguy]

You and I must be distant relatives or something. I too consistently seem to get that errant flier. I do it so consistently I don't count it as part of a group when working up a load. What's really annoying is four out of five almost in the same hole and then that other one about an inch away. Especially since the four in one hole is so rare to begin with.

[stagpanther]

You and I must be distant relatives or something. I too consistently seem to get that errant flier. I do it so consistently I don't count it as part of a group when working up a load. What's really annoying is four out of five almost in the same hole and then that other one about an inch away. Especially since the four in one hole is so rare to begin with.

Doesn't seem to matter how many with me;; up to 5 anyway, 2 out of three, three out of four and four out of five will be close. As soon as I get a good group going--the pressure is on to finish well.

Low BC pistol bullets using a volatile charge of AC9 is tough enough to begin with, I'm still pretty happy with these results, the bullet arrives at 100 yds with more energy than most any load out of a pistol barrel leaves with. The felt recoil is tremendous for a charge of under 15 grs. of powder; something along the lines of a stout 308 load IMO. While still far less than something like a 458 socom, it still is "disconcerting" knowing it's coming from a diminutive cartridge like the 10mm--which I still think should be called "minimag."

[stagpanther]

I finally got around to developing some "hot" full power cartridges with the 180 gr golden sabers and ran into a few issues with the set-up. First, the hyperfire hipertouch has a marked tendency to double tap--meaning fire on trigger pull and reset when firing the "full power" loads. This particular trigger group was discontinued--I suspect I found out the reason why. Shooting the same loads through my other 10mm lower with a different trigger group and stock assembly does not double-tap. To be fair, the odin Zulu pistol stock has some kind of dual recoil spring arrangement which I suspect may play a role in possibly inducing something akin to bump-fire.

In addition to this, the new starline cases would split at the web even at loads that were under full-power. For a while I thought something in the hand loads was creating a pressure issue, but other than the split in the case, there were no other pressure signs or indicators of unusual expansion. I eventually figured out that the pistol buffer set-up was simply too light--and the carrier was extracting the case before it had time to relax in the chamber, thus tearing them in half. I pulled the 5 ounce pistol buffer (Odin says pistol buffers should be used in the Zulu) and replaced it with a 10 ounce carbine buffer and the problem went away--though the felt recoil is noticeably more pronounced, which is to be expected I guess.

Bottom line, I think with a 10mm PCC that does not involve a gas system the buffer/spring assembly must be tuned to the power and burn characteristics of the cartridge--I think that even CMMG's 10mm PCC with delayed unlock comes with a set of different buffers to tune for the level of power for the load being fired. As for the hipertouch trigger group--I'll pull it and put it in a lower with a conventional stock/buffer set-up and see if the double-tap still happens.

[9x19]

Welcome back.

Thanks for the update on your 10mm trials... It confirms my DI 10mm upper from RMW is one of my better investments.

Have a great Thanksgiving!

[davidsog]