Home Forums Hunting & Shooting AR and Tactical Rifles My 10mm hunting carbine project

With having been wanting a 357 lever action for a while, and perpetual backorder and crazy price increases when I never seem to have the money when I do come across one, I decided that I would just make a 10mm AR carbine instead. I mainly wanted it to hunt whitetail with, and the distances that I get to hunt here in the Appalachian mountains, I generally can't get more than about a 65 yard shot anyway, and typically is inside 35 yards, I wanted to try the 10mm.

While I haven't gotten to hunt with it yet, I think it's going to do really well. I've been able to work up some handloads with it and am getting very respectable velocities with both 155 and 180 gr pills. ~1770 fps with the 155s (which is over 1k ft lb--near what a 5.56 at 2950 fps energy is) and the 180's are just over 1550 fps (960 ft lb). The 175 gr hardcast is very near the same as the 180's. Close enough that I'm not even going to get out my notes on it to write the numbers down here.

I'm sure that should do pretty good on a deer.

When I was making it, I wanted to do some changes to try to improve on it.

For starters, the Chip McCormick trigger I initially used was too light and there was a couple of occasions where the gun was rocking on a bipod and doubled on me. So, I stopped shooting and replaced it with a heavier Rise Armament LE415 trigger, which solved that.

Another main reason why I wanted a trigger with a "cassette" style housing was to better reinforce the interior pocket of the gun. Since blowback pistol calibers are notorious for wearing hard on fire control pin holes. And since I generally load on the spicy side of my reloads to start with, I didn't see how it could hurt anything trying to make it as rigid as I could inside of there.

Another thing that I did, which was probably overkill, but I also made a steel plate that I put on the exterior of the lower around the trigger and hammer holes. It's just a thin piece of sheet metal that will reinforce the outside of the trigger pocket too. Since I added some width to each side of the lower, normal hammer/trigger pins weren't long enough to reach through each side fully and seat flush. So, I got some 5/32 stainless steel rod, cut to length, threaded the ends and used it like the KNS antirotation or other antiwalk pins that are on the market. The hardest thing about that was not breaking the tiny #4-40 tap trying to thread the little holes.

Again, all of the reinforcement of the fire control pocket may not be necessary, but when I make something, I generally try to improve it any way that I can. Since I made it to be a work gun, my kids or grandkids may end up with it someday and I want it to still work as good 75 years from now as I do this fall when I'm using it. So, I spent a little extra time on it than I normally would have.

While it looks like simple antiwalk pins, the steel sheet on the exterior acts in the same manner as KNS antirotational pins since both the hammer and trigger pins are both supported with the same piece of steel. Plus the cassette style fire control box internally, that's improved the best that I could think to do it.



Next issue that I worked on, since I am loading pretty hot, was to calm the ejection down. It was spitting the empty shells out probably 15 feet away. Which is excessive by any stretch of the imagination.

Aside from using a 308 cal flat coil chrome silicone buffer spring (which helped but still didn't resolve it completely), I tried a 10oz Kaw Valley buffer.

While that too helped, it still wasn't as good as I wanted it to be. So, I decided to do a rifle length stock. But since there are no super heavyweight rifle length buffers, I had to make my own mods to it too.

I used the 10oz KV buffer that I started with, but added a rifle length extension onto the buffer weight to bring it to the correct length that the rifle buffer needs to be. This also added about 2-1/2 more oz to the buffer weight making it very close to 12.5oz now, helped keep the bolt closed longer and slowed it down and make ejection more acceptable.



I later added a sleeve to have the buffer spring seat further rearward than normal which increased the pre-load a little more and again, helped with ejection.



Since I'm old, I remember the ban years when we couldn't own collapsible stocks and such. I'm still partial to rifle length stuff anyway because they just feel better shooting, but also, I have kinda long arms and rifle length fits me better. I have owned several Ace skeleton stocks and have always loved them. I especially appreciate the foam cover over the tube on cold wet mornings in the woods when I am about to snuggle in on a shot in the tree stand. So, I made this one similar to it and used the foam cover, but I used an extra gearhead works brace on the back of it and I pretty much made my own ace style ultralight stock for it. Since money is tight these days with how much inflation there is and gas prices and grocery bills, I'm just making due with what I have right now and not going out and spending a lot on a commercial stock when the one I did works for me. With all the extra weight that I added in the back of the gun, it's surprisingly almost nearly perfectly balanced in front of the receiver where the barrel meets.

After shooting it after those improvements that I made, I must say that it shoots good and feels good and I'm overall happy with it now. Recoil is no worse than any other AR that you'd shoot and overall the muzzle is surprisingly stable when you pull the trigger which may help with a quick follow up shot if I need to. With any luck, I'll find out soon enough how it does.

[img]https://i.imgur.com/3vnKbWE.jpg?1[/img]

Very nice!

Thank you sir. It's just something I enjoy doing.

Well done! I have been looking at a 10mm build, but the hotter loads flinging brass into low orbit was an issue. This gives some good ideas to try on my build, so much appreciated!

Great. I'm glad that I could get a few folks thinking outside the box.

It's just impossible to find rifle length buffers for pistol caliber weights and stuff. So, I stood over my lathe for a few minutes and modified my own to work.

Even though the brass still landing around 9 feet away (when shooting max loads) it's much less with commercial stuff. A lot of it is loaded pretty anemic unless you go with buffalo bore or one of the other places that actually make 10mm the way it was intended.

But, the longer travel on the bolt, feels so much better when shooting. The whole gun just feels better.

I know many people are going with CMMG banshee, and I understand that. It does seem like a better mousetrap than straight blowback. But, I was already in the process of making this and saw it through. Overall, I'm happy with how it turned out. It shoots good.

Sweet project... I love seeing stuff like this...

I never did a 10mm... thought about a 9x25 Dillon.

I did 45acp (subs) and .460R (cookers)

Very cool CashisKing. I've done a few other pistol caliber carbines, but more for HD roles. One of which is also a 45acp. I have even considered loading up some 450 SMC loads for it from some cut down 308 brass. But then I'll be in the same situation as I would be with 10mm. The 10mm would probably over-penetrate too bad in close distances, and I have to be really careful about that. The regular 45+P should do well.

Fun caliber for sure... both the .45acp and the .460 Rowland.

The Rowland is about 99% of a .44 Mag on performance (but at those load levels... one and done on brass).

More pics please John... projects are very cool.

I respect any man that plays with stuff.

Sure. Both my other pistol cal AR's are very unorthodox. It's pretty safe to say that there's not another like either of them anywhere.

I've designed and built my own suppressors for the bigger part of 2 decades now and I enjoy making integrally suppressed guns. The 9mm AR and the 45acp both are that way.

As I said, no one has ever done another quite like them as far as I know.

I have been using the freefloat handguards as the registered suppressor tube since it houses everything. The AR9 is made more like an MP5SD and goes back over the ported barrel like the mp5 does, and the AR45 is more like the Delisle internally (which I have also made a copy of) and several others including 300blk and 9x39, 22lr's, etc.

Here's my 9mm AR integral (old pics/vid with the brace still on it)





And the 45acp integral. It was a bigger challenge how to pin/weld everything together to bring it to legal lengths, but I managed to do that so I can use a stock and not have to double stamp the gun. Of course, the silencer(s) are registered.

[img]https://i.imgur.com/gey4kq0.jpg?1[/img]




I just enjoy doing it. Some guys are good at wrenching on cars and can go 1/4 mile in a few seconds. Some can paint thought provoking pictures. Some have traveled to outer space and the moon.

Love it or hate it, I just like fooling with my stuff.

SWEET!

This is my .460R version



Working on a 10" .458 SBR AR-10 with these 720s and 730s



Mag is the problem... will try and solve this winter (3D print a single stack maybe?)

Projects are fun...

All are legal with stamps...

Wow, those are some beast cast bullets. Those almost weigh as much as two 1 ounce 12 ga slugs.

I'm not even sure what twist rate would be needed for a bullet that long/heavy. I'm assuming pretty fast.

And I understand about needing to have stamps for a bunch of stuff. In having my FFL's for 9 years, and with as many stamps as I have for some of the stuff I've made, I realize doing it legally is a lot safer bet than trying to do it without paying their extortion fee....er, I mean, tax.

Mostly I run 350 FTXs (feed and function)... the 730 are just a fun OMG sub first round. Brass is ANY belted magnum cut off at the shoulder or less (i.e. I use split neck .300WM and 7mm RM "reject" brass and cut it off. Think .458 American or shorter. I call it the 458 CAT (short for "Catastrophe") because is possible to chamber my rounds (2.800" COL or under) in a .308 or .338 bore Weatherby.

The 730 subs won't stabilize much past 35 yards (I have tried 1:10 thru 1:20). The bolt gun is a .458WM. The AR-10s are .458 Lott. Jump does not effect accuracy in big bore. The 350s are supers and hammer like .45-70s. In fact, I clone all loads in .45-70 (i.e same data).

Edit... when I was proof testing the 730 concept (rifle strapped to a tree with a long string... this hole happened... That is a can of snuff for scale.



Anyway... back to your project... Great stuff... Post more. Apologies on the side-track.

https://mechtechsys.com/

I’ll just leave this here.

Nothing wrong with a mechtech or converting a 1911 over to a carbine.

That wasn't the direction that I tend to want to go though.

CashisKing, no apologies necessary. I enjoyed seeing it.

Be careful with MechTech barrels. Chamber support specifically.

I have owned Mechtech... but when I pulled down to thread and rechamber to Rowland (that used to be an for sale option)... I sold out... and did the QC10s