Preparing barrel for a sight extension / bloop tube

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Shooterer
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Preparing barrel for a sight extension / bloop tube

Post by Shooterer »

I am adding a MEC Berta 2 extension to my 1913. This is my first time using a tube, do I need to prep the barrel in any way before installation?

The extension will not be removed frequently because it will fit in the case with it on.

I don't want to take it off later and find the barrel finish ruined. Should I be considered?
Last edited by Shooterer on Mon Jun 18, 2018 7:23 am, edited 2 times in total.
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Modena
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Re: Preparing barrel for a sight extension / bloop tube

Post by Modena »

You should be removing it everytime to clean it.
Tim S
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Re: Preparing barrel for a sight extension / bloop tube

Post by Tim S »

Assuming the extension has been machined for your barrel, not just that make, it should fit snuggly not too tight. If you need to pound it into place, stop. Either your measurements or the machining weren't right. I did put tape around one barrel, but I was swapping a tube from another rifle.

Modena is right that tubes should be removed for cleaning. The manufacturers realise this, and build in some way to accurately replace the tube. This can be a separate collar that stays on the muzzle, or a guide pin. I think the Bertha has a collar/ring behind the clamp.
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conradin
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Re: Preparing barrel for a sight extension / bloop tube

Post by conradin »

What is the reason for taking the tube out and clean it as opposed to leaving it on and clean it? If the tube is not a compensator (no vent) then I thought it would make no difference as far as the how you clean it? If there are vents I would understand because that means you can only clean it in one direction...
Tim S
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Re: Preparing barrel for a sight extension / bloop tube

Post by Tim S »

Conradin,

The primary reason is to clean the muzzle. It's a good idea to wipe the muzzle of any 0.22 rifle after shooting, but it's really important for tubed barrels, as the muzzle get much dirtier. Although the flat muzzle face doesn't touch the bullet, the propellant gas does adhere, as it's contained by the tube. The crud can build up quick, enough to choke the muzzle. There are reports on this forum of plugs of fouling being found on neglected tubed barrels.

The tube itself needs a clean, otherwise the diameter slowly tightens, and the surface toughen, both affecting the flow of gas around the bullet.

A 10 or 12bore shotgun boresnake or rod is the right size to clean most tubes. I use a wad of toilet paper, or rag, and a squirt of solvent if I clean the day after shooting. Hot soapy water might work, and would be safer for carbon fibre tubes.
Last edited by Tim S on Mon Jun 18, 2018 5:04 am, edited 1 time in total.
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Modena
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Re: Preparing barrel for a sight extension / bloop tube

Post by Modena »

As well as cleaning the tube, the primary reason is to clean the most important place on your rifle for accuracy - the crown.
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