Thread: cutting a 16 inch carbine barrel to 12 inches

Originally Posted by Bill999

Im thinking the shorter barrel is going to fuck my Dpt modular can in no time tho, the problem with that can is you can open it up and have a look inside at the wear. on my other cans Im blissfully unaware of how fucked they are

Ill work on the picture that shits hard.

Interested to see your findings on the DPT can. Trying to get time to go up and see him for a spare 223 and also chech out a new 17HMR can. The modular aspect is real No 8 ingenuity stuff.

the dpt can is great totally worth it.

the modular aspect is cool, I took two of the three baffels out and tryed it. gets louder allright.

the can works great, made the mistake of taking it off, whoa 12 inch barrels bark.

im thinking of grabbing a couple of spare baffles for when these ones wear out incase dpt changes his design.

just shot a couple of possoms with it, I can see me using it heaps, seems like the hold back sorted its self, but time will tell

yea valid point about the adjustable gas block not putting more gas out, Ill look at softening the spring and opening the hole in the gas block up before i drill out the barrel mostly because Im not sure how i will get the swarf or what ever its called from out of inside against the rifeling.

not interested in hand loading for this tho chasing brass out of a ar15s hornady training ammo is the go for me

Be careful opening the gas port. Do it in very small steps. Can't put it back again short of buying an adjustable block.

Don't mess with any springs or anything but the gas port.

whats the difference between the carbine buffers and the normal?

Originally Posted by Bill999

whats the difference between the carbine buffers and the normal?

Carbine buffers are designed to be run with carbine length (shorter) buffer tube and spring. You are running a rifle (longer) tube/buffer set up. Don't know if you were contemplating it, but mixing and matching isn't really a solution. Carbine buffers are lighter, but designed to work with the shorter tube travel and different spring resistance.

Your best bet is probably to get in touch with a good gunsmith, and get them to sort your gas issues out. Spending a hundred bucks or so now to get it running right after the barrel chop, might be a heap cheaper than if a mix-n-match buffer set up damages your lower, or too big a gas hole gives you pressure problems that snap a bolt.

seeing as I am running a new carbine barrel and my buffer is set up for the factory mid length gas system a carbine buffer may be the tiket, I just want to know are they stiffer in the spring department or softer?

Originally Posted by Bill999

seeing as I am running a new carbine barrel and my buffer is set up for the factory mid length gas system a carbine buffer may be the tiket, I just want to know are they stiffer in the spring department or softer?

Just to make sure we're on the same page here.

Are you are running a mid-length gas system, or a carbine length gas system on this rifle now? I'd thought all the DD barrels coming in were carbine length gas.

The pictures of your rifle show you are running a rifle a2 stock. That means you're almost certainly running a rifle length buffer tube/spring/buffer.

You can't run a carbine buffer in a rifle buffer tube. All you will achieve is the destruction of your lower. The same goes for running a carbine spring in your rifle tube, that too will see the bolt gas key smashing into the rear of your lower every time you pull the trigger.

You're really at the point where you need to go see a gun-smith, or someone who knows a lot about getting the AR platform to perform. Is it really worth stuffing your rifle for the sake of a couple of hundred dollars? A new lower will run you a lot more than that.

I believe that a rifle-length buffer system and a carbine-length buffer system are similarly bufferly. I have had both on my rifle and it functioned identically with no perceptible change in recoil or brass ejection.

I suggest measuring the gas port size, and opening in tiny increments by an actual competent person with extension function testing - key words 'actual competent person' and 'extensive function testing'. Worst case: you get it done by an actual incompetent person who does not perform function testing and makes it oversize and you need to buy an adjustable gas block and tune it back down. It sounds like it's only just fractionally under gassed if its functioning but mags aren't locking the BCG back. Could also be the mags, try some different mags before you do anything.

these are previously perfect functioning mags in that lower/upper/every thing except the barrel/gas tube.

Id say yea fractionally undergassed some times its perfect others it dosent lock back. never fails to pick up a round.
ill let it see if it sorts its self out. and realighn the the gas block.

the problem is I live rurally and have to post away any thing away to get it fixed, and Im a tutu so usually I just sort things out myself
Youd probably scoff if you saw my home made barrel wrench

If you shoot it a loootttt the gas port erosion might sort it out?

yea sounds like a plan, spend that $200 on bullets and go shooting, it cycles it just dosent lock back, so basically functional just not ideal

It will take a looootttt of shooting to get any significant gas port erosion