Gunsmithing question.. a barrel extension pin "should" be pinned INTO the barrel right?
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Obviously not on a Krieger;-) I'm guessing you were holding the bbl and not the upper. You should be able to screw it back together tight and if it doesn't cause the headspace to be short or gas port misalignment, run with it.
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Its from Brownells, so lifetime warranty... And I just got it..
Sent from my Nexus 4 using Tapatalk
Sent from my Nexus 4 using Tapatalk
And this is why I love brownells, they just called me back and they are next day air the replacement barrel and a return shipping sticker to send the old one back.
Sent from my Nexus 4 using Tapatalk
Sent from my Nexus 4 using Tapatalk
I don't torque an ar barrel with barrel clamped. I pin the receiver into a fixture and torque the nut. I haven't seen any extensions pinned just torqued onto shank. As long as it indexes properly at the shoulder when torqued up and gp lines up i would run it. You should be checking headspace whenever you torque a barrel on anyhow.
I torque my barrel nut extension on to the barrel to 100 ft.pounds and then drill into the threads and pin in place. The pin and nut can still be removed if need be but it won't turn off and this has worked well in .223 and .308 gas gun builds.
so your saying it should not be pinned, and the pin is there just for looks? ......
The pin serves one purpose. It clocks the barrel extension with the upper receiver. That's it. Purpose is simple. Failure to index the extension means the lugs are out of position which would result in guns firing out of battery and/or failure to chamber and lock.
There's no other function. Since the extension is snugged up to 75+ ftlbs there's little risk of it rattling loose over time. The pin when installed in the extension and barrel is redundancy that isn't really needed. I do my personally owned AR barrels just like this because when I cook a throat I can set it back without having a hole in my threads. A rev or two does mean that the gas tube will reach into the gas key a bit more, but usually there's enough "float" room so that it doesn't crash into the bottom. With some calibers, it can upset the bolt timing a bit as the pulse gets shorter, but this is usually limited to bigger bore type stuff in the subsonic range.
Different doesn't mean wrong.
Brownells service IS some of the best in the industry. That said don't think your not paying for it. Returns are built into their cost/profit models just like anything else. The benefit for the company by NOT bickering over every little thing is that it cultivates more sales by reaching a broader audience due to the excellent reputation.
A service in any capacity costs money.
just saying.
C.
There's no other function. Since the extension is snugged up to 75+ ftlbs there's little risk of it rattling loose over time. The pin when installed in the extension and barrel is redundancy that isn't really needed. I do my personally owned AR barrels just like this because when I cook a throat I can set it back without having a hole in my threads. A rev or two does mean that the gas tube will reach into the gas key a bit more, but usually there's enough "float" room so that it doesn't crash into the bottom. With some calibers, it can upset the bolt timing a bit as the pulse gets shorter, but this is usually limited to bigger bore type stuff in the subsonic range.
Different doesn't mean wrong.
Brownells service IS some of the best in the industry. That said don't think your not paying for it. Returns are built into their cost/profit models just like anything else. The benefit for the company by NOT bickering over every little thing is that it cultivates more sales by reaching a broader audience due to the excellent reputation.
A service in any capacity costs money.
just saying.
C.
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so your saying it should not be pinned, and the pin is there just for looks? ......
Hope you read Chad's post. Your answer;-)
I didn't realize any big makers were actually drilling and installing the indexing pins thought the extensions into the barrel threads, is Krieger doing this?
I make my own indexing pins, cut to length so when installed in the extension, against the crest of the tenon thread below, its at the correct height so as not to interfere with the barrel nut. Every pin I've ever purchased retail was this length already.
I did have a friend once who didn't realize this was normal. He drilled into the barrel tenon thinking the indexing pin was supposed to secure the extension and barrel together.
The end result was a disaster. The pin was now significantly deeper and didn't have enough "pin" protruding above the surface of the extension. When he was torqueing the barrel nut into the upper, the barrel/extension/everything began rotating in the upper and the indexing pin ate a groove around the inside of the upper as it rotated!
I didn't realize any big makers were actually drilling and installing the indexing pins thought the extensions into the barrel threads, is Krieger doing this?
I make my own indexing pins, cut to length so when installed in the extension, against the crest of the tenon thread below, its at the correct height so as not to interfere with the barrel nut. Every pin I've ever purchased retail was this length already.
I did have a friend once who didn't realize this was normal. He drilled into the barrel tenon thinking the indexing pin was supposed to secure the extension and barrel together.
The end result was a disaster. The pin was now significantly deeper and didn't have enough "pin" protruding above the surface of the extension. When he was torqueing the barrel nut into the upper, the barrel/extension/everything began rotating in the upper and the indexing pin ate a groove around the inside of the upper as it rotated!
U might want to slow your ducati down a bit and read all of the OP's post and Chads. Had Krieger pinned thru the extension into the bbl tenon I doubt this thread would exist.
The moral of the story is;-) Don't hold the bbl. Hold the receiver!
In my opinion, you basically miss-handled the installation and managed to un-ass the barrel extension. Using the wrong tools and wrong technique is the problem, not Brownells or Krieger.
Barrel extensions do not need to be “hard pinned” into the barrel threads. You should always be holding the upper receiver in a properly designed fixture and always be turning the barrel nut without anything trying to grip the barrel. The upper and barrel nut are not concerned with the barrel at all, only the barrel extension.
If the extension had not loosened and started moving, you probably would have screwed up the pin slot in your upper receiver. Then you would have had to send your receiver back because it was “faulty”.
Also note that NO AMOUNT of torqueing on your barrel nut is going to change the headspace on a gas gun. That is set in stone when the barrel extension is fit and torqued into place on the barrel before the receiver is even in the same room. The headspace exists either “in spec” or “out of spec” totally independent of the receivers. It is a function of the barrel extension/chamber and the bolt. The receivers simply hold these two assemblies sorta close together so they can do their job.
Two demerits. Do not pass GO. Do not collect $200.
Did I misread the OPs post when I was "or wasn't" reading it. His barrel is from Brownells right?
My Ducati is doing just fine as I read both the OPs post, and Chads. Both of them.
First post says: "this just unthreaded as i was torquing the barrel nut on.."
Second post says: "Obviously not on a Krieger;-) I'm guessing you were holding the bbl and not the upper. You should be able to screw it back together tight and if it doesn't cause the headspace to be short or gas port misalignment, run with it. "
To which I reply " I didn't know any big makers, like Krieger, were pinning extensions into tenons".
Perhaps my meaning was overly ambiguous?
I can easily comprehend why the OPs technique failed to produce the desired results, provided the extension isn't pinned to the tenon. However when the second post stated "Obviously not on a Krieger;-)", I took this to mean that he believed Krieger pins extensions to tenons.
Being an 07/02 (mostly mfg custom suppressors) who does a fair amount of AR work, including some Krieger barrels, I've never ordered one that was finished, only as blanks so that I can headspace and install the extension myself.
I was hoping someone else would chime in and verify weather or not Krieger pins their tenons/extensions together, as the second post implies. I guess this is your way of chiming it to verify what I thought I already knew. Post #2 is wrong and Krieger does NOT pin extensions to tenons.
Perhaps I was too ambiguous, my wording wasn't articulate enough to be easily understood.
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That aint showing off. That's respect!
This Fat, old guy can still get it done too although your certainly going a whole lot faster than I ever have.. Jason Pridmore school in Pueblo, May, 2008
Then there's this little biche. I'm more afraid of it than the 1000. One of a kind Italian Phantom GP pocket bike. THIS bike allegedly won the worlds in 2009. Got it from a guy in GA a couple years ago who supposedly went to Italy and bought it from the guy. Dunno, but it hauls ass and irritates the police to no end.
This Fat, old guy can still get it done too although your certainly going a whole lot faster than I ever have..
Jason Pridmore school in Pueblo, May, 2008
Then there's this little biche. I'm more afraid of it than the 1000. One of a kind Italian Phantom GP pocket bike. THIS bike allegedly won the worlds in 2009. Got it from a guy in GA a couple years ago who supposedly went to Italy and bought it from the guy. Dunno, but it hauls ass and irritates the police to no end.
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Pure 2 stroke heaven!!! . Nothing like the sound, and smell of a 2 stroke gp bike.
I got to turn a couple laps on an RZ500 once!! Sounded line being chased by a gang of pissed off weedwackers!!
. Nothing like the sound, and smell of a 2 stroke gp bike.I got to turn a couple laps on an RZ500 once!! Sounded line being chased by a gang of pissed off weedwackers!!
My head is spinning;-)
#2 post says they are not pinned. U say it's wrong while agreeing????? ;-)
2nd post actually doesn't say that its not pinned. It says "obviously not on a Krieger". Since the first post said "extension spun" and second said "obviously not a Krieger, I too this to mean (possibly mistakenly, i'll admit) that the extension couldn't have possibly spun on a Krieger due to its being pinned to the tenon.
Perhaps I simply misunderstood his statement. I rarely misunderstand machines, but I misunderstand people more often than not!
2nd post actually doesn't say that its not pinned. It says "obviously not on a Krieger". Since the first post said "extension spun" and second said "obviously not a Krieger, I too this to mean (possibly mistakenly, i'll admit) that the extension couldn't have possibly spun on a Krieger due to its being pinned to the tenon.
Perhaps I simply misunderstood his statement. I rarely misunderstand machines, but I misunderstand people more often than not!
Just pokin' fun as usual.
I assumed that you would know that the threads would be screwed up if the pin went into the tennon.
As they said back in school! When you assume, be prepared to assume the position ;-)
I'll try not to make that mistake again ;-) Dumbass!
