# Threading a bull barrel gun --internal threads question???



## Twenty five ought six (Dec 28, 2009)

Off the wall question.

Reading the thread on threading a .22 barrel for a suppressor.  The external threads have to be protected I assume with some sort of nut/blank.

Has anyone ever tried using internal threads on a bull barrel?  I have a bull barrel Ruger, and there is plenty of metal to do this.

If you could do this, it seems that there is some security also in not advertising that you're gun is set up for a suppressor.


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## usmc2112 (Dec 28, 2009)

In my military gunsmithing days I saw several archived pictures of firearms with the suppressor threads inside the barrel and know for a fact it is possible.  The two problems you run into with this set up is shooting without the suppressor leads to fouling the threads which makes it hard to attach the suppressor without first cleaning them up by running a thread chasing tap over them.  the other minor setback is the last 1/4 inch of the barrel and the barrel crown is the most important part as far as accuracy is concerned.  Any alteration to these parts would severely effect point of impact and mechanical shot repeatability.  the solution would be a well thought out design and fancy lathe work, then it would not only be possible but would work quite well.  and you would have a the best of both worlds.


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## Cknerr (Dec 28, 2009)

USMC is correct,
I would also like to to point a possible problem with shock wave reflection. If you have a deep well for threading and attaching there is a potential problem with the set up. The walls will reflect the shock wave and theywill hit the bullet. This is okay if you are really good and accurate with your machining. If not, your bullet will get pushed a little to one side. Not good for accuracy!

Keep the well as shallow as conceivably possible. There are a few barrels with enough diameter where the well can be wide enough (even then best to keep shallow) this won't happen, most bull barrels aren't wide enough. 

Since it is easier to attach things to the outside, this problem is rarely encountered, and if it is - wonder how many people would be aware of it. 

Best of luck,
Chris


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## Hammack (Dec 28, 2009)

I did one a couple years ago for a friend when we installed his muzzle brake.  It was a bull barrel.  .875 across the muzzle.  If I remember correctly I cut them about 1/2" deep or a little less, and I used a fine pitch tread, and it has done fine although I don't think he has ever shot it with the brake uninstalled so I can't comment as to whether accuracy was effected with the attachment uninstalled.


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## bighonkinjeep (Dec 29, 2009)

An extended choke tube type thread protector may  ease some of the affore mentioned problems. Though this is purely theoretical.


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## Twenty five ought six (Dec 29, 2009)

bighonkinjeep said:


> An extended choke tube type thread protector may  ease some of the affore mentioned problems. Though this is purely theoretical.



Kind of what I was thinking.  A short compensated extended choke tube type protector.

I have a Dan Wesson that has an integral compensator with a blank area in the shroud ahead of the threaded barrel.  Only drawback is that you aren't supposed to shoot lead bullets (.44 man/.445 Supermag).  It will lead up the compensator holes for sure.

Thanks for the responses.


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