Barrel Fitting and Lockup Question

[Wakaba]

I am going to fit my new to me Huntsman .50 bbl to my '87 SB1 frame I have owned since new (parents bought me a 12ga at age 10).  I have read the various stickies and how-to's but being my first fitting, I am a bit hesitant to get it right the first time.

There is very very little gap at the breach.  When I say this, I can't get a .002" feeler gauge in there.  Light can barely be seen through the gap, and only at the perfect angle. 

With barrel on frame, and forend mounted, hinge is nice and tight.  Locks on closing but just barely, as the release button doesn't 'pop' back up.  I am thinking I need to shave down the locking shelf on the barrel...

any thoughts?

[MSP Ret]

if the barrel locks up and there is less than .002 at the breech end it sounds as if you are good to go as is with the Huntsman barrel on that frame. There is very little if any pressure on the breech face of the frame in a ML, the pressure is contained by the screw in breechplug. I would shoot it as is and enjoy it, If any problems come up, and I doubt they will, adress them then, do not go filing anything yet.....<><....

[Busta]

Wakaba,

If it is closing up tight TDC (top-dead-center), and not locking at the shelf, I would say it needs a little work. You sure don't want it popping open on you while shooting, you still have a carrier and a primer that has to be held in place by the standing breech.

You could smoke the shelf with a candle or put a thin layer of white out on it to see how much engagement you aregetting from the latch. Just make sure to read the FAQ's for pop-open-medicine, sounds like that is where you are going to be at. Have you tried closing it firmly to see if you get a little better engagement?

Have you tried it with a primer carrier installed? Primer? Check again with your feeler gauge.

[Wakaba]

Thanks for the help guys...

I smoked the latch and found that the face was only getting about .003" engagement with the frame's latch,  hence the lockup issue.  I took a file to the latch shelf on the barrel end and I am getting a good solid positive lockup now.  The lock's overlap is now in the .25" area, which is where my factory fitted 12ga barrel on the same frame was at when I smoked it last night.  Breach face is now perfectly flush with less than .001" clearence. 

I have a Hubbard's 209, and a .25acp breach plug as well.  I am going to see which one I prefer after I find a place that will let me shoot this thing

[Hammerspur]

I have a Hubbard's 209, and a .25acp breach plug as well.  I am going to see which one I prefer after I find a place that will let me shoot this thing

I've been watching this thread, glad things worked out!

Many years ago before I belonged to any range/Rod & Gun club I used to go to a spot on a powerline I'd picked as my own private range.
Was easy to get to where it crossed the Interstate. I'd pull off the shoulder in my truck and brush-bust up onto the service road then in about 1/2 mi. to where my measured out range and high backstop hill were located. Kept a folding target stand I'd made there hidden in the undergrowth.

I don't know where you live but I'm in RI... smallest state and 2nd most densely populated I think.
If any one heard the shots off in the distance they couldn't tell from where, there was no danger of stray ricochets getting to the residential areas so all was 'Jake'.

Much developement occured since then and the place wouln't be any good for those uses now. Some woods remain and I sometimes run my dogs there for exercise.

I can still see the gray blemish on the perpendicular face of a boulder at about 120 yards from my former shooting spot. I used it once as a target for sighting my first deer gun... an old H&R 162 12 ga. smoothbore w/rifle sights.
Shot 5 boxes of Federal 1 1/4 oz. slugs that day from my home made portable bench and they all hit in a group about the size of a large dinner plate... not too bad, accuracy wise anyway.
All those 'fire plugs' out of that lightweight and from a low bench, WHEW!
Sure taught me to snug that buttstock to my shoulder I'll tell ya'!