Lenght of a barrel extension tube?

Moderators: pilkguns, Marcus, m1963, David Levene, Spencer

TWP
Posts: 384
Joined: Sun Mar 14, 2004 6:57 am
Location: Northern Virginia

Post by TWP »

Call Bill Earnest.

He makes tubes with a built in barrel tuner. Basically a small brass weight that can be moved back and forth in the bottom of the tube. That way you can adjust the tube to tune the barrel harmonics.

Bill Earnest
570-797-4872

Oh and it should cost you much less than $300 from him as well.
C-son

Post by C-son »

Thanks for all the help guys. I forgot to tell you that it is a special made two-part tube with 1) a fixed mount on the barrel, and 2) a removable tube with the same height for the foresight as the mount (like the "Tenminator", but lighter). In 3P I dont use the tube in standing, so therefore I wanted this special feature without changing my POI to much.
Thats why the price became a bit higher...

Still, I awaited your comments before ordering it. Perhaps I will look into the barrel weight first, since recoil-reduction is my main purpose - and it looks like a tube is the wrong recepie for that.

Once again - thanks.
can shooter

tube comments

Post by can shooter »

Hi guys

I installed a 8 inch tube on my 1913 and had great results, call it luck with harmonics ets. being effected. I did it for a better sight picture, as i could open my front site to a 5.7 mm with the tube extension. I matched the ammo to my barrell with the tube installed, and managed a 10.5 mm group ave from outside edge to outside edge.

One mistake I made was not to clean the barrell end after each shoot. I would just take the long piece off and clean that, and not the coupler piece. The grit and junk left pitted my front of my barrell, once i realised this, cleaning after every shoot is now part of my routine.

I torque my screws 3.5nm, as more is likely to strip the aluminum thread. i would be very carefull to torque the screws the same for each shoot. one addtion i made was to install a set post in the barrell to match a small slot in cut in the tube coupler, that allows for an excact fit every time, and limit the sighting in by not getting the tube on in exactly the same place.

good luck with your tubes.

Regards

Can shooter
Old Grouch

Post by Old Grouch »

Having done a lot of testing and measurement of barrel motion, with very high speed electronic micrometers (up to 10 KHz frequency and 10 microinch resolution) I can tell you that an extension tube will change the motion. Maybe good or bad, depending on a lot of other things. Ditto tuners. If set right, they help. All of which depends on (but not limited to) temperature, humidity, altitude, and bullet velocity. There is no advantage to a longer sight radius, unless you have very little accomodation in your eyes (can't easily change focus, mostly older shooters). Then the tube helps, puts the front sight closer to 'infinity', you see it and the target a bit better. The drawback is it makes the front globe seem smaller and amplifies barrel motion. Consider using the larger (22 mm) front sight assembly. A lot of junior shooters use or want to use tubes, without any idea of what they really do. Bottom line, if you can see better with a tube, use it. Make sure you scale your front aperture up by the increase in overall sight radius.
Hawkyork
Posts: 2
Joined: Wed Sep 19, 2018 6:03 am

Re: Lenght of a barrel extension tube?

Post by Hawkyork »

Old Grouch- I like and thoroughly endorse your reply. All the important points covered.An England shooter and coach has the opinion that long extension tubes are a ‘fad’. He does use a 5” standard Walther tube on his KK500 TR but sees no need to go longer. My experience is ; unless you have a fantastically steady hold, the more visible ‘wobble’ that the long tubes show up, tends to delay the final release ( waiting for the ‘perfect’ picture) and encourages ‘snap shooting’ where you take the shot as the sight moves through the target. Having bought a 10”” tube from a uk tube maker (Barry Nesom) I swallowed my pride and moved the sight back towards me when I found my results had got worse with the sight right at the far end of the tube. The much more stable sight picture ( movement still there but less visible) meant I got a satisfactory release picture quickly and my results went back up. The increased sight radius did improve the clarity of the foresight but also the accuracy improved (cf pistol short sight radius with rifle long sight radius). Obviously matching foresight diameter ( plus using 22mm foresight tunnel) to get the right white/ black/target relationship is personal but supremely important. I have taken 2 years to refine the best sizes including thickness of sight ring. As with everything in this sport experimentation, trial and error and attention to detail produce results. We might not all have the natural talents of Olympic shooters but we can reduce the differences by application. Good shooting in ‘24 from across the pond!
Tim S
Posts: 2023
Joined: Mon Jan 03, 2011 11:33 am
Location: Taunton, Somerset

Re: Lenght of a barrel extension tube?

Post by Tim S »

Hawkyork,

You do realise this thread is 16 years old. I don't think any of the original responders still post here.
nicolas G
Posts: 21
Joined: Mon Oct 16, 2023 7:30 am

Re: Lenght of a barrel extension tube?

Post by nicolas G »

This is an old post but it's good to be reminded of the basics. The latest posts are very interesting.
Post Reply