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2/3/2005 10:18:32 PM EDT
Installing TAPCO piston in NHM90. Can it be threaded all the way tight or backed off a bit before drilling for pin. I noticed the original piston was just short of being all the way tight. Thanks.
2/4/2005 4:17:52 AM EDT
[#1]
Right most pistons have a little wobble to em....
2/4/2005 4:59:56 AM EDT
[#2]
Wobble can be a good thing.  Loose tolerances are happy tolerances.
2/4/2005 6:10:55 AM EDT
[#3]
Yes, You want to back it off about a 1/2 turn before pinning it.
2/4/2005 1:07:55 PM EDT
[#4]
I recently installed a gas piston. I think 1/2 turn would be too much.I ran the piston up and down into the bolt carrier to chase the threads.Then I ran the piston down till it bottomed out and backed it off about 1/4 inch.So it had a small wobble to it.Then I drilled through the piston (PITA) and when I finished peaning and dressing up the ends the play was like the orginal.I shot it many times after doing the work and it works just fine.
2/4/2005 9:03:28 PM EDT
[#5]
Select Fire, I assume you meant 1/4 turn rather than inch. Thank you and you other good folks for your help. Happy shooting. Dogear
2/5/2005 1:20:06 PM EDT
[#6]
Turn
2/7/2005 10:05:50 AM EDT
[#7]
After you drive the pin out, line up the holes and see how far you can turn the piston in before it bottoms out.

I checked several, they averaged 1/2 turn, I had one that was almost 3/4 turn.

I have used 1/2 on all my builds and all run great.
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