Shiloh Sharps 38/55 Not Stabilizing

  • 752 Views
  • Last Post 21 January 2024
Gordon posted this 05 January 2024

Have a recent acquisition of a shiloh sharps 38/55 with a 34 inch barrel, 1 in 16 twist. Cannot get it to stabilize, have tried 2 different weight projectiles at 320 and 365 grains and different powder loads from 43 to 49 grains of Wano 2p.

I have more than 30 years of Black Powder experience with Gibbs, 45/90 Remington Rolling Block, 40/65 Sharps. All using my own cast bullets with good results, winning many events out to 1000 meters. 

Have used 20:1 and 30:1 alloys   Plus 365 grain BACO Creedmore and 320 grain CBE molds

Please Help

Attached Files

Order By: Standard | Newest | Votes
4060may posted this 05 January 2024

black powder?

bullet length?

velocity

a .375 bullet, at 1300 fps, 1.25 long requires a 1-14.5 twist to stabilize

a 1.125 long bullet at 1300fps will stabilize with 1-16 twist

according to Greenhill formula

Attached Files

Ken Campbell Iowa posted this 05 January 2024

also, 38-55 is notoriously suspect of incorrect bullet fit in throat and main rifling. 

as a co-incidence i am currently making a bump-up die for a 38-55 that " tumbles " 0.378 castings ... needs 0.382 or so ...

hah, this one is flying sideways at 30 feet from muzzle ... kinda neat ...

ken

Attached Files

Glenn R. Latham posted this 05 January 2024

Ken, do you have any of those Starline 2.125" cases.  They have thinner necks for fatter bullets.

Glenn

Attached Files

  • Liked by
  • Ken Campbell Iowa
Ken Campbell Iowa posted this 05 January 2024

Glenn ... good idea ... might need those thinner necks.  this is an old 94, i think 1895 or so ... still has rifling in front of throat tho ... kinda ...

Attached Files

Tom Acheson posted this 05 January 2024

A very good friend and I each bought a Model 74 from CSA in late 2009. CSA was a 3-month wait and Shiloh was almost 2-years. Mine chambered in 40 cal 2 ½ and his in .38-55. Mine with iron sights and his a scope. We shot a few NRA silhouette matches together.

 

He was recoil sensitive so he used Unique and 5744 powders, with an NEI bullet weighing 340-grains. Surprisingly he hit and knocked over the steel rams @ 500-meters. His barrel was made by Badger and used the standard CSA chambering. He never mentioned problems with bullet fit. He was a “CB only” shooter since 1982.

 

Today I have a Remington Rolling Block in .38-55 that shows a preference for an NOE 330-grain bullet and 4227 powder in a 1:12 twist Green Mountain barrel. I did have a friend run a throating reamer through it to help reduce the “forcing cone” angle and allow the bullet (fixed ammunition) to enter the chamber a bit farther.

 

Tom

Attached Files

  • Liked by
  • RicinYakima
  • Bud Hyett
Aaron posted this 06 January 2024

Simply put, you have some discovery work to perform with your 38-55. Slug the bore, determine the actual twist rate yourself, and definitely make a chamber cast. Once you have established the critical measurements, you can assemble cartridges based on that factual data, not the supposed data. The chamber cast is essential since there are different reamers for the 38-55. You are probably assuming that Sharp's used a SAAMI reamer.

I have Uberti, Winchester (1903, 1997, & Miroku) and Bullberry guns in 38-55. You guessed it! There are 5 different cartridges and 2 different bullet sizes used. I can shoot a Bullberry cartridge in any of them since he uses a .375 barrel and a shorter (SAAMI) chamber.

Once you get the factual data, you can dial that puppy in and start shooting wonderful groups with the appropriate crafted ammunition. As mentioned above, Starline offers two versions of their 38-55 brass. Yup, I use both.

G'DAY

 

With rifle in hand, I confidently go forth into the darkness.

Attached Files

  • Liked by
  • admiral
  • Bud Hyett
Tom Acheson posted this 06 January 2024

What Aaron suggests about determining critical dimensions yourself is good advice. When I started messing with my Roller, I mistakenlty determined the bore size and started out sizing the bullets at 0.379"....too fat. Redoing the examination I found that 0,376" was the correct size. Accuracy really improved with the "smaller" bullet.

I called CSA and asked for a drawing of the reamer that they used in my Model 74 and they sent it to me. These many variables and knowing and understanding them, are the steps to good results and are key to enjoying our hobby.

Tom

 

Attached Files

  • Liked by
  • Bud Hyett
linoww posted this 07 January 2024

Yup, I have 4 guns in 38-55.None are similar in bore/groove dimensions, twist  or throating.

"if it was easy we'd let women do it" don't tell my wife I said that!

Attached Files

Gordon posted this 08 January 2024

Hi Aaron,

Thank you for your feedback. I think that I have the information you required ... Barrel diameter is 365, the rifling grooves are 374.  I have tried bullets sized at 375 and 376. Rounds used 365 grains and are 1400 long, and 320 grain at 1210 long. I double, double checked the barrel and it is definitely a 1:16 twist.

Attached Files

Aaron posted this 08 January 2024

Man that's a tight barrel. I believe the issue is the chamber throat diameter to accommodate a cartridge with whichever chamber reamer was used on such a tight barrel. I suspect the problem lies there. May I suggest you try loading up some 255gr cast bullets or commercial 270gr. .375 bullets to see how they shoot? My Bullberry barrel at 16" twist shoots 255gr and 270gr cast just fine. All my other barrels are 18" & 20" twist and shoot 255gr all day. I have never attempted to shoot bullets as heavy as those you listed. My long range rifles are chambered in 45-70 and 45-90. The 45-70 is a SS Sharps and the 45-90 is a lever action. The 45-90, a Win 1886, is twisted to shoot the 330gr Express Bullet at 18". The 45-70 is 18" as well.

My gut instinct is telling me that you should stick with the shorter brass (2.080") since you will not be sizing bullets of any weight to accommodate a bore >.375". I suspect the throat is too large for the "unnaturally" tight bore/groove diameter.

Perhaps some of our Sharps 38-55 shooters can chime in here with opinion?

 

 

With rifle in hand, I confidently go forth into the darkness.

Attached Files

Aaron posted this 08 January 2024

Just doing some math, results show the 320gr pill would use a 17.4” twist and the 365gr would like a 15” twist. According to Steve Garb and Mike Venturino, they feel a 2” faster (tighter) rate would be better with an appropriate alloy. Another place to look is in the CBA Journal for match winning recipes with the 38-55.

Black Powder Cartridge Reloading Primer, Steven P. Garbe & Mike Venturino, 9th Edition 2017, p18

With rifle in hand, I confidently go forth into the darkness.

Attached Files

Ken Campbell Iowa posted this 08 January 2024

for testing a shorter bullet reasonably cheep, Lee has a mold that works good in 3 or 4 of 38-55 for me.  Lee 379-250 RF ... 

actually, it's castings work as well as any of my much more expensive molds in these 38-55 .enigmas ...

****************

but also the 38-55 is a hoot when you get it workin right ...

ken

edit..  RF, not RN for Lee mold.

Attached Files

Aaron posted this 08 January 2024

Ken is spot on. The Lee 379-250 works great in my rifles.

 

With rifle in hand, I confidently go forth into the darkness.

Attached Files

Aaron posted this 08 January 2024

To add more clutter to the discussion:

Uberti claims that the Cimarron M94 Winchester they build in 38-55 uses 1:18 rifling.

The description on the MidwayUSA web site for the same rifle claims it has 1:12 rifling.

My measured rifling is actually 1:20 in that rifle which just so happens to be 2" LESS than the Greenhill formula result of 1:22 for the 250 & 260gr bullets.

Looks like Garbe & Venturino are spot on with their observations and that may be why the 250gr and 260gr bullets work so well.

And on another note, your bullets may be stripping. Had you thought of that as well?

Tom Acheson is running a 330gr bullet with a 1:12 twist. He is using smokeless however which doesn't have the BAM factor on the bullet base. Could be his are easing into the bore rather than getting pounded there with black powder?

 

 

With rifle in hand, I confidently go forth into the darkness.

Attached Files

4060may posted this 09 January 2024

FWIW

I have shot BPCR since 1991, Class is AAA in the NRA

my first rifle was a Rolling Block, Douglas barrel, 1-16 tw, 40-60 Maynard, 396 gr bullet,SAECO greaser, 58 grains of GOEX CTG, Fed 210GM primers, Chrono 1140 FPS, just stable to 500 M, tried 1000yds, wind drift was about many feet.

second rifle is a Remington Hepburn, 38-50 Rem.Shilen barrel, 1-12 tw, .376x.265,  with a 1.4" long NEI , 386gr bullet, I shot 59 grains of GOEX CTG, F150 LP primers, Chrono 1237 fps. stable to 500 M, with a 340 grain, 1.35 long, 59.3 grains of 9/05 Goex FF, 1377 chrono

only shot  the NEI bullets in competition once, not for me, sold the molds, my friend made a mold for me using the Dan Theodore, design,

more accurate and consistant

all the loads use a .060 poly wad

my experience with WANO powder was in a cartridge gun, the velocity was about 10% slower than GOEX

the Greenhill formula indicates 1800 fps, with a .375 x 1.4" bullet, to stabilize, with 1-15.6 twist, close to 1-16

http://kwk.us/twist.html

HTH

Chuck

Attached Files

JeffinNZ posted this 09 January 2024

How does the lack of stability manifest itself?

Can you post photos of the bullet holes?

Cheers from New Zealand

Attached Files

Wilderness posted this 09 January 2024

A friend had a Winchester commemorative .38-55 with matching ammo.

Then bought a CBE mould 300 gns plus.

Pulled the jacketed bullets and replaced with cast heavies.

First bullet came out off zero and sideways - took out both screens of my Oehler.

Attached Files

Gordon posted this 13 January 2024

Hi thank you for your input i will be trying goex fff as i have some by the sounds i have to push them faster. Hopefully i can get to the range next week cheers Gordo 

Attached Files

belongtotom posted this 16 January 2024

I had the very same problem with a Pedersoli Hi-Wall clone in caliber 38/55 .Poor group size and bullets hitting sidways at 100 yards.  After a lot of shooting and head sratching , The answer turned out ,to be the length of the cartride case .Try the shorter case ,ie one formed from .375 Win . This shorter case proved to be the answer in my case  Good luck and enjoy your 38 Tom

Attached Files

  • Liked by
  • Ken Campbell Iowa
longhunter posted this 16 January 2024

Your bullets are to long and to Heavy.

Jon

Jon Welda CW5 USA Ret.

Attached Files

Gordon posted this 16 January 2024

Hi Belongtotom what weight bullets are you using cheers Gordo

Attached Files

4060may posted this 16 January 2024

Gordon

this will shed some light on it, actual shiloh shooters

https://shilohrifle.com/forums/viewtopic.php?t=17857

Attached Files

belongtotom posted this 16 January 2024

The bullet I ended up using is a ,Lyman single cavity mould #378 674 CV , Alloy is 1-25 and the as cast whgt is 336grs. , The powder is 4198 ,Cartridge cases are the short ones OAL of 2.015 , I also could not get 5744 powder to shoot without leaving a lot of unburned powder in the barrel ,especially in cold weather  

 

Attached Files

  • Liked by
  • Bud Hyett
Premod70 posted this 21 January 2024

If using plain base bullets in a 16 twist barrel your maximum bullet length should be in the vicinity of 1.10 in which will put it in the 280 grain weight limit. You can increase the velocity and get a little more bullet but I doubt you will see little if any gain other than a bunch if aggravation. Good luck on your venture.

Forrest Gump is my smarter brother.

Attached Files

Categories
Search
Popular Tags
This Weeks High Earners
Hot Topics
Close