AmericanLongRifles Forums

General discussion => Tutorials => Gunmaking tools and techniques- metal shaping => Topic started by: Rolf on June 04, 2011, 06:24:58 PM

Title: Please, could someone do a tutorial on correct drum installation?
Post by: Rolf on June 04, 2011, 06:24:58 PM

There has been several threads pointing out the dangers of incorrectly installed percussion drums. I've looked through my gunbuilding books and can find very little info on correctly installing percussion drums.  I'd like to learn more about:

1.Interference fitting
2.use of internal shoulders and chamfers
3.and what ever else is important for safe installation.

Best regards
Rolf

Title: Re: Please, could someone do a tutorial on correct drum installation?
Post by: Hoot AL on June 30, 2011, 05:02:48 AM

Rolf,

I have a couple links that I hope will help you. The first one is drilling out the barrel for the drum. In my case, I was installed a homemade drum, but the principle is the same.

Link: http://www.hootalrifleshop.org/drum_install.htm

At the bottom of the page on this link are a few photos showing how I located the proper positioning of the nipple on the drum for the hammer to strike it. I used an 1/8" dowel the same length as my nipple.

Link: http://www.hootalrifleshop.org/inlet_lock_b.htm

I assume you have a drum jig for drilling out for the nipple.  If not, go to Track of the Wolf.

AL

Title: Re: Please, could someone do a tutorial on correct drum installation?
Post by: Acer Saccharum on June 30, 2011, 03:04:10 PM

Do not remove the drum for cleaning purposes. It wears the fit, and pretty soon, the drum turns past where it was originally set.

Put a cleanout screw on the end.

Fit the lockplate tight on the underside of the drum. This adds much needed support from the impact of the hammer.

Tom

Title: Re: Please, could someone do a tutorial on correct drum installation?
Post by: Dphariss on June 30, 2011, 04:46:24 PM

In my personal opinion the term "correct drum installation" is an oxymoron.

However, it should be made of a good quality HOT ROLLED STEEL or cold rolled that has been brought to critical temp then quenched and then completely annealed.
If you buy a drum its cold rolled. I have never seen a hot rolled modern drum.
There should be a slight radius to the cut where the body diameter is reduced to the thread diameter.
The threads on the drum should be a minimum clearance fit to the threads in the barrel.
The drum should be fit tight to the side of the barrel with a significant shoulder with 100% contact with the barrel flat.
The lock must be placed so that there is good contact between the lockplate and the drum to keep the shock off the threaded shank of the drum.

But I would still use a patent breech.
Recreating poor designs from the past is simply recreating poor designs of the past.
Dan