kurtm

Isn't grill paint a high temperature coating? The aluminum carrier in my original CTR-02 from 1998 is well into it's second barrel so I would say with good maintenance at least 15,000- 20,000 rounds, but I haven't killed it yet.

The final word on aluminum carriers is......They are light! Oil them up good every stage or so and they will last a couple of barrels worth of shooting at least.

Well to make a long reply short... No, I do a ventriloquist act with ponies and knife throwing.

Ammo is in general more expensive and harder to find, but just for fun and you got the ammo, sure.

Information, maybe, but not data.

With page after page of inertia info on this forum this is what y'all came up with? Does said M2 have a pistol grip stock on it? Is it exhibiting bolt bounce? Is the cam pin ok? Is the cam pin and slot lubed? Are the locking lug recesses clean?........and about 30 more things? I really doubt you are "out running" your Benelli unless you are at .14 splits or less.....and yes that has been quantified, or for some real strange reason "buckshot" makes you pull the trigger slower!

Strange mine is still there after 12 years. Sorry it didn't work out for you. I bet the epoxy worked.

I agree with TitoR. I have seen a good many Benellis fail. In the hey day of 3-gun there were tons of "how to" videos on modifications, and I used to cringe seeing some of the crap they were doing. It got to the point I could walk down a gun rack at a match and pick out the ones that probably wouldn't make it through a whole match. That and utter lack of maintenance and lubrication brought plenty of Benellis to their knees! That said gun to gun moded right and maintained the Benellis are a far better gun and in general work much better than most any other. They sure outlast anything else out there.

"No one says We have a bingo" ....... you just say Bingo". Lt. Aldo Raine.

Unfortunately that is the recoil spring not the inertia spring Cobra. As for inertia springs, I defy you to find any two that are the same. Wire size and length vary quite a bit for a spring that size.....gotta love Q.C. Italia! But you can find INERTIA springs quite readily for fairly cheap.

P-Tex melts around 400°, general shooting won't harm it. The problem with epoxy is it isn't easy to trim as P-Tex, but it sure would be a viable option, as well as long as you grease up your containment barriers so you don't epoxy stuff onto the barrel

Hmmm.....that didn't work so well! Anyways here goes again. I had a rib dovetail that I had to fill as well. I went to ski shop and got a couple of sticks of P-Tex in black. It is a plastic used for ski base repair. I clamped a couple pieces of aluminum on each side of the cut and filled in the notch with the molten P-Tex, then after it cooled trimmed it all up with an exacto knife. Might be worth a shot for your needs. BTW, you light P-Tex and it melts and drips.

Still waiting on your numbers. We will accept any cubic meter, cubic millimeter, or centimeter, cubic inch, yard, old French pounce........ or you have no idea of what your talking about, which we learned talking about barrel extensions. Expertise by DELL.

Ahhh, got it! Excruciating, but obviously no concept of the topic, but man, with a key board!!!! Gotta love the experts on the web!!

Ahhh..... You have "assembled" over 50 AR type rifles from parts others built, got it. Extensions are sold separately so someone can take a barrel blank from a blank supplier, turn it to what ever profile they wish, do all the work to thread, chamber, drill gas port etc. and then either assemble their own upper, or sell the completed barrel assembly to someone like you who then assembles an upper. That's why extension are sold separately.

Wrong place, this is the volume thread, the one where you state you always work off volume. If one works off volume all the time and most of the components that make up an upper are constants, I would suspect one might be able to come up with measurements on volume, so what is the volume of gas in a less than 16" AR-15? I'm guessing there should be a number in cubic inches or any other type of volume measurement you wish, but it should be a number. Also if one is using volume one should be able to tell us how much volume of gas is created when a cartridge is discharged, once again a number, and they should be able to tell if that volume would fluctuate cartridge to cartridge.

So how much gas volume do you have in a less than 16" barrel. Is it different for a 16" barrel or a 20" barrel? If so by how much? Is gas volume dependent on the powder and primer in any given cartridge?

Extensions are not "pinned" to the barrel! From my post above, one of us is obviously machining barrel blanks, threading, chambering, setting head space, torquing on barrel extensions and drilling gas ports. I'm not at all confused as to what happens, what steps to do in what order, nor how it is all assembled or correctly head spaced to a bolt, but you have me at a disadvantage! Why would you ever re-drill the extension pin hole when it is installed in the exact place it needs to be from the extension manufacturer? I am also sure that you have missed two steps in your headspace example if indeed you messed up your measurement while machining the threads and cutting the chamber in the first place. Can you tell me why you do it the way you do it in your shop?

A few shot of a barrel and extension I am putting together.

So K-Tex, are you saying you can change the head space on an AR with a barrel nut shim? That is what you just said above, you need to revisit how it all goes together if you think this. The extension is screwed on to the barrel, the barrel is headspace to the extension and torqued to around 135-150 ft/lbs, no nut involved! The extension comes with the pin hole already drilled it IS NOT drilled latter. The extension is the part that fits into the upper receiver, not the barrel, so it really goes like this.... receiver, extension, barrel (already screwed on to extension and headspace), shims....if needed (almost never by the way), and then barrel nut. Here is a picture of an extension waiting for a barrel to be threaded, chambered, headspaced, and screwed on.

I'm pretty sure that the barrel extension is that little notched thingy at the back of the barrel that the bolt locks into and has those feed ramp cut thingys. It is screwed on to the back of the barrel to the tune of 135-150 ft/lbs. In the olden days if an M1 or M-14 barrel didn't torque up and time correctly, they had a fixture that had three big rollers that could be tightened around the shoulder of the barrel and then the barrel was rotated effectively swaging a bit more material into the shoulder area so it could reach torque and timing kind of like the punch idea someone suggested. Now that said I have also had a barrel back off from the extension and I red lock-tited the crap out of it without a shim and shot another 4-5 thousand rounds out of it with no problem, so I would think your fine. Also I'm pretty sure a barrel nut shim fits under the barrel nut on top of the shoulder of the extension which is that little ridged thingy with the alignment pin sticking up out of it. It would never work as a barrel extension shim. It might help align a hand guard/ gas tube, but it is not going to shim the extension.

What's 10 pros among friends? 930, 940, whatever it took.

Just like a Thanksgiving dinner......you gotta work off volume! Pressure is released by the "gas tube", but the volume stays and stays

You can always cut a small clearance window around the gas block if it's too close. As for must have adjustable block....nah! I run my Aluminum carrier fully gassed and it is a very flat rifle. I found that I seemed to be waiting on it if I turned it down, but to each their own.