New Barrel Problem

[jeff]

Just tried out a new 20"   223 Bullberry barrel and I'm not too happy with the results.  While there is almost no vertical play, there sure is horizontal play when the action is closed.  The problem seems to be at the hinge pin.  Groups stink!

Now, on ther other hand, my original 10" and 14" barrels both lock up nice and tight with no play.  

Any suggestions?

[iiibbb]

http://www.bellmtcs.com/store/index.php?cid=1

if they won't replace the barrel... perhaps a new hinge pin?

[Thebear_78]

bullberry has a accuracy garantee, send it back.  Chances are that they will make good on it.

[jeff]

Hey there iiibbb and Thebear!

Thanks for the ideas.  I measured, and re-measured and then put on the bi-focals to make sure that I was seeing what I thought I was seeing.  What a surprise!  Seems like the old contender has gotten a little loose over the years, think I got back in '81.  I checked the link, and am ordering the oversize pin.  Never would have imagined that the pistol would have gotten so loose,  I need the .376" pin.  

Guess that's not so bad, as my waist size has increased a lot more during the same timeframe.

It's great to be able to tap into the collective wisdom that's available in cyberspace.

Thanks again...

[jeff]

Chris
 
Thanks for responding. and I appreciate your advise.
 
Perhaps I am missing something, but in this particular instance, the looseness is a very noticeable sideways wobble, to the left and right.  Not up and down which I would attribute to a problem with the locking lug.  
 
At this particular time, it seems that the movement (of my displeasure) centers around the hinge pin.  I measured, and my hinge pin diameter is .373"  while the frame indicates almost .376".  That .003" difference in diameter is really a lot!  It means that the barrel can deviate .006" in either direction on the horizontal plane (thats .012" overall)  and up to .003" in the vertical plane.  The oversize pin is supposed to measure .3752" and that should take a lot of the slop and wiggle out of the system.  
It should reduce wobble to .0016" vertically and .0032" horizontally.  What really makes this a nightmare is that the longer the barrel, the greater the deviation.  
 
Based upon the dimensions that I'm currently dealing with there are  no alterations to the frame or barrel.  I don't know how T/C could possibly have a problem with that.

Or at least that's what I am hoping to achieve.  Otherwise, I'm out a few bucks and still have the same problem to deal with...

[jeff]

Chris

If the pin replacement dosen't work I'll give Fred Smith (Bullberry) a call and I'm only out the price of a pound of powder.  The step after that would be to discuss it with T/C.  I'm a little reluctant on that because they'd probably change the hammer and who knows what else.  I do not have any plans to actually alter the frame and I have the older style with the sliding bar safety and just plain don't want any changes.

[jeff]

I received the two oversized pins that I ordered sunday nite this afternoon.
A .3752" and a .376" pin.
 
Wow!  What a difference!  I tried the .372" pin first, it just slipped in with no problem at all.  No problem with lockup, release and the slop was noticeably reduced but not eliminated.  So I decided to see if the .376" pin would have any effect, understanding that the instructions indicate that the hole would need to be reamed.  Another surprise!
 
The .376" pin went in one side of the frame and partially into the barrel pin hole with a slight amount of thumb pressure.  I used a mallet and tapped it in  completely.   The operative word is 'tapped'  I did not beat it into submission.  
 
To late to go to the range to test, but I don't feel any of the side to side wobble anymore.  Frame s/n is 2137xx acquired new in the early 80's with a 357 mag 10" barrel.  Perhaps 4-5000 rounds of mild loaded 166 gr wheel weight bullets.  In the past 12-14 years it's just sat in the case.  Maybe 200 rounds of my old loads, then about 200 rounds of 7-30 Waters (cast bullets).  

I hardly think that the frame has been abused or overly stressed from the recoil of shooting.  Is it possible the hinge pin hole got bigger from opening and closing or was this a case of  loose tolerances.

[ra]

I also had a 22" Bullberry barrel that had a lot of side to side movement, as you handled the carbine you could feel the movement of the barrel.
There was a problem with that barrel that it was not built as ordered and the barrel was replaced.  The replacement barrel was even looser as it had side to side and also up and down movement. I have 3 frames an this barrel was loose on all of them.

I swapped out the locking lugs with  some from another barrel and the up and down movement went away, side to side movement was still there.
I then installed an oversize hinge pin an now the barrel locks up tight.
I have not measured the holes in the frame but several other barrels lock up tight with factory hinge pins on my frames.

[iiibbb]

Cool... glad it worked

[jeff]

iiibbb
 
I think that I'm partially there, the proof will be what happens at the range.
 
 
ra
 
I never noticed any slop with my 10" 357 factory barrel.
 
My 7-30 Waters is a 15" Bullberry there has (retrospective view) some lateral looseness.
 
My sensitivity to the lateral slop became accute with the 20" Bullberry, and that's where I started investigating.
 
Went back and checked the other barrels and the results were the same.  The longer the barrel the more movement at the muzzle and the easier it is to see and feel.  The more muzzle movement, the larger the groups.
 
I'll report back on this thread the results of my range tests.  
 
Fingers crossed...