Page 1 of 1

barrel length to keep bulk pack 22 subsonic?

Posted: Mon Jan 17, 2022 2:35 pm
by mr fixit
Getting ready to play an integral 10/22 build. Finally getting around to some drawings and suggestions that Capt. Link made for me a good bit back. My main question is that barrel length prior to the suppressor core will keep most bulk pack .22's subsonic for lots of grins. From what I can find, it looks like around 4-5 inches should do pretty well. Does that sound about right? any other suggestions or information I should know?

Re: barrel length to keep bulk pack 22 subsonic?

Posted: Tue Jan 18, 2022 9:30 am
by Capt. Link.
I'll look up velocity vs barrel length for you. I would recommend porting for velocity control over a short barrel. Did I give the print a name? I may have some updates for you.

Re: barrel length to keep bulk pack 22 subsonic?

Posted: Tue Jan 18, 2022 9:13 pm
by Historian
5.5" barrel length was what the esteemed PTK used on his 10/22 SBR
" It was not a BB gun"

Hiram Percy Maxim is smiling.


<< https://www.youtube.com/watch?v=fyBNJ_31uQc >>

So sweet!!! :)

Look forward to your presentation.

Re: barrel length to keep bulk pack 22 subsonic?

Posted: Wed Jan 19, 2022 12:02 pm
by Capt. Link.
I would start with 6.00" as barrels and chambers very. If you have a chronograph set the velocity @ 900-950fps or for a maximum of less than 1000fps. The suppressor itself can boost the velocity so be aware.

A trigger and action job will improve any build. Bedding the "action/barrel" will help. A custom barrel should be considered.

Re: barrel length to keep bulk pack 22 subsonic?

Posted: Fri Jan 21, 2022 2:26 pm
by T-Rex
My 4.5" AR22 will sometimes get Fed Bulk to go super.
With my 4" MKii, I never hear them do so.

Re: barrel length to keep bulk pack 22 subsonic?

Posted: Fri Jan 21, 2022 8:34 pm
by mr fixit
Capt. Link. wrote: Tue Jan 18, 2022 9:30 am I'll look up velocity vs barrel length for you. I would recommend porting for velocity control over a short barrel. Did I give the print a name? I may have some updates for you.
not sure on a name, i'll look. it did have the cross jetting ports in each chamber.

Re: barrel length to keep bulk pack 22 subsonic?

Posted: Sat Jan 22, 2022 12:22 pm
by Capt. Link.
T-Rex wrote: Fri Jan 21, 2022 2:26 pm My 4.5" AR22 will sometimes get Fed Bulk to go super.
With my 4" MKii, I never hear them do so.
Hey T long time.
I can't do as much research as I once did but chambers make a huge difference in velocity. As the ammo itself is so filthily ensuring complete combustion is a consideration in a build. I have been using a BENTZ chamber that was developed for automatic actions. Its a tapered chamber that holds the bullet tight in the front for good alignment to the bore and loose in the rear so feeding and extraction is excellent. I think it the best "match" chamber ever made for a auto. The velocity from this chamber is higher as the bullet is held under tension longer than typical with better combustion resulting in less fouling.
Its the fouling that lead me to use longer barrels and porting for velocity control. A few small ports very close to the chamber feature high pressure so they stay clear plus barrel length past the ports allows any residual powder and gases to combust before the baffles are encountered. This more complete combustion lowers FRP and the longer barrel is more accurate when you put it under tension.