Criterion No4 barrel

[Rwsgunsmithing]

Well I figured I'd start a new thread to actually talk about the barrels themselves.

I'll post pictures and updates on what I find here.

Last night I slugged the bore so I can confirm bore dimension. .3135-.303 Please note that measuring the slug can be very difficult so I'm gonna say there is possibly a +/-.0005 accuracy variance.

5 groove barrel

Checked front sight fitment with 2 front sights and both fit very nice with one needing a few light taps with a rubber mallet.

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[Peter Laidler]

Front sight fitment......... Or do you mean the fit of the foresight block band onto the barrel?

[Rwsgunsmithing]

Yes the front sight base/block band onto the barrel.

[Rwsgunsmithing]

Tried 3 bayonets tonight and all fit. 2 were tight with one 2nd variation fitting fairly loose.

Did run into one issue though. The barrel is easily over timed with the barrel being threaded hand tight onto the action. Looks like I need to either find a new action to use or find some breaching washers.

Does any one have any leads on some washers?

[Peter Laidler]

I wondered when this indexing might rear its ugly head. And this IS going to be a problem or a concern for all. You will all have to accept that the question of over or under indexing was common across the board when we berreched up barrels. The difference is that we had a rack of 20 or so new and perfect but used barrels and tried them all until you found the closest one that you could breech up tight with.

There was an underturn/hand tight spec (of 17 degrees springs to mind but don't quote me.......) but after a few times, you just got to know what barrel would breech up well.

There is an answer and I mention it in an earlier thread. AND IT'S NOT SWAGE THE EDGES!

On the other hand I could have told them all this for the cost of a phone call!

[bigduke6]

Did run into one issue though. The barrel is easily over timed with the barrel being threaded hand tight onto the action. Looks like I need to either find a new action to use or find some breaching washers.

I,m glad you mention this Robert, as Peter mentions above, I,m guessing a lot of folk are thinking it will be a case of " take out the wrapper, breech up and all is well "

Regarding washers I had quite a few but these were made the same width (+ a few thou) of a parting off tool I had, recovering a few good barrels at one point and knowing that the chances of the timing not being correct on another action I made a relief cut on the barrel (also made it easy for removal)

After the barrels were cleaned up it was a case of measuring the gap with the barrel in the correct position on the donor action and grinding the washers to suit (I was lucky having access to a surface grinder at the time).

**Still an easy job to do but without a surface grinder, the machining has to be precise or it will be a labour of love with a surface plate and grinding paste.........

**(I mention the surface plate etc, because its my preferred method, it is easy to take the required meat off the barrel, but by the time you set it back up in the lathe etc to take the X amount off, set the barrel back up in you blocks fit washer plus action and find your still out can be a PITA..... and not wanting to teach folk how to suck eggs but if your doing something of this nature make sure all the bits and your measuring equipment are in the same place etc, temperature can have an amazing effect on metal and measurement )

[Peter Laidler]

There's a much easier way Big Duke............ Incidentally, this isn't a new issue at all. It was a well discussed issue for ages and that's why, if you could, you'd always try barrels with the D-in-a-circle mark first. They were ........... Anyway!

[bigduke6]

Understand the easier way Peter, it was just the way I had used the parting off tool..... made sense at the time to make a few oversized washers etc, could be an interesting thread though as I,m waiting to hear the word "shim" .....

[Peter Laidler]

You mean the dreaded word 'shim'!

[bigduke6]

You mean the dreaded word 'shim'!

I was just being polite, one question (can't remember if it has been mentioned) for Robert and others in the Know are these barrels with an undersized chamber or finished chamber ??