Uberti 1873 SSA Frontier 44-40 from 1995 Cylinder Chamber Mouth diameter to larg

[Palatine Tom]

Dear all,

As mentioned my 44-40 1892 El Tigre is doing fine with 6.5/7grain Trailboss/ or 33grain Ffg and .428 lead bullets

My next challenge is now my Uberti SSA Frontier 44-40 from 1995

Its barrel is .428 BUT the cylinder chamber mouths are .434!!! 

With this set up none of my tests with 6.5/7grain Trailboss and .427, 428, .429 and .430 lead bullets showed any positive precision results..

Any ideas how i can solve this .434 chamber mouths problem

Thanks for your kind help

Tom

[ndnchf]

What brass are you using?  Winchester is typically thinnest at the mouth, Starline and Remington are thicker.  But I don't recall which is the thickest.  Get the thickest ones you can find, that should help make up for the large cylinder holes.

[w44wcf]

Tom,
How hard are the bullets you are using? It is possible that a pure lead bullet and b.p. would bump up to fit the throats.

A standard .433 / .434" bullet if it would chamber (try thinner brass as ndnchf indicated) would fix the problem.

Also using a hollow based bullet would likely give good results.  These are a bit expensive though....
http://www.buffaloarms.com/Detail.aspx?PROD=157241&CAT=4135

Here's another that is less expensive..
http://www.mattsbullets.com/index.php?main_page=product_info&cPath=70&products_id=280


w44wcf

[Gripmaker]

Greetings Tom,  It doesn't sound to me that your cylinder mouth dimensions are large enough to be that concerned with, especially with the old open-top barrel/frame attachment.  Your problem may be in the alignment from the cylinder to barrel. If they are not properly aligned, your bullet will enter the forcing cone at an angle and have to be FORCED into alignment. This leads to alot of inaccuracy problems and can be corrected by having the barrel forcing cone "TAYLOR" throated. The tools can be secured from Brownells for not much or any good gunsmith can do it for a reasonable cost. I have a Ruger Bisley that has .4345-.435 cylinder mouths and she shot 1 1/4" at 25 yds. I had her "throated" by Hamilton Bowen and she now shoots 5/8-3/4" at 25 yds. and will stay on an 8" plate at 200yds. Using dead soft lead bullets will soften the impact force of improper alignment but not eliminate the effects as the bullet is still "cock-eyed" going down the barrel. After throating the barrel, I would suggest you use the thicker Starline brass and a fairly soft bullet to eliminate as much oversizing of the cylinder mouth as possible while allowing the bullet to swage into the barrel smoothly. This is a trick used by long-range pistol shooters and it works quite well.
Have a wonder-filled 2014. God Bless and shoot safe.
Gripmaker

[Palatine Tom]

dear all,

first of all have a great happy new year 2014.

thank you for your hints so far. it is not so easy to find soft lead bullets in germany but the search will go on.

alignment cylinder to barrel is just fine this should not be the problem. however my gunsmith should check the forcing cone for heavens sake.

this saturday i made some bp catridges with 33 grain ffg and a .429 220 grain lead bullet. as mentioned the precision was not so good BUT the boooom was impressive!!  Is there a chance that i may harm my colt clone??

have a great year

tom

[Gripmaker]

Tom,  I doubt that you will do any harm to your gun with that load. I have some that are 36 gr. of Swiss 3F which duplicates the original BP load in velocity and things have worked great. As for your cylinder alignment: the alignment may be OK but as long as the cylinder bore is larger than the barrel bore, there will be some misalignment. There is no way to stop that. However, by cutting the forcing cone longer (into the barrel), the bullet will be more correctly aligned before it contacts the lands and grooves in the barrel. The measurement for length should be 1/2 the dia. of the bullet as a minimum, at an 11 degree angle. Every gun that I have had this procedure done on has had it's groups cut in half at the very minimum.  Please let us know how things come out. God Bless and shoot safe.

[Palatine Tom]

Gripmaker,

Thanks for that input.

My best load combination so far is .428 200grain lead bullets (silvermoly/molybdan coated) with 5 grain trailboss - its not perfect but with your hint to extent the forcing cone,  its hopefully the correct way forward.



greetings

tom