1873 Winchester: accurate 357 rifle load w/rimrock 158g rnfp?

[Litl Red]

BTW, nobody has yet mentioned that lever guns sometimes need freeing up.  Hanging the magazine and forearm on the barrel can be poorly done.   

I had a premium priced Marlin some years back that had a very poorly fitted forearm.  At first I thought the forend screws were locktighted in.  While relieving that I noticed the magazine tube looked bent.  It was.  For some reason, the sucker shot a whole lot better after cleaning up that mess.  That was back before Remington came along and supposedly lowered the quality.   

[JeffinTD]

That's an idea. It looks beautifully built but it would only take a moment to check the forend fit.

I found some 125 jhp Speers I must have had to fire form 357 Herritt, so I loaded up a few.

My thoughts currently are to check out the forend and fire it one more time from the bench, then let Winchester have a go at it. 

On the plus side the new Vaqueros I picked up are very accurate with pretty much anything and are a pleasure to shoot- especially after I put in Wolff spring kits... 

[JeffinTD]

Well, nothing seems misfit with the forend.

Fired it today, just from a field pod.

Rnfp rimrock 158 over 3.7 trail boss shot into about 5".

Just for giggles, same load shoots into a bit over 4" with the Vaquero revolver. 

Same bullet over 15g 2400 shot into 3". Not sure what the velocity is, but way over max for cowboy action. 

125g Speer JHP over 17g 296 shoots into around an inch from the rifle, under 3/4" if you don't count one flier.

Same JHP load in the Vaqueros also shoots into about 4".


So bottom line, the rifle doesn't seem to like 158 grain cast bullets of any brand, with any powder I can find.   The revolvers will shoot 158 gr bullets reasonably well. 

The rifle does like lighter jacketed bullets with full power charge of slow burning powder.


I guess it is time to try some lighter cast bullets.

[Litl Red]

............
125g Speer JHP over 17g 296 shoots into around an inch from the rifle, under 3/4" if you don't count one flier.

Same JHP load in the Vaqueros also shoots into about 4".


So bottom line, the rifle doesn't seem to like 158 grain cast bullets of any brand, with any powder I can find.   The revolvers will shoot 158 gr bullets reasonably well. 

The rifle does like lighter jacketed bullets with full power charge of slow burning powder.


I guess it is time to try some lighter cast bullets.

Glad you found that out. 

Bullet stability is directly related to rpm or how fast the bullet spins.  The longer or the heavier the bullet, the faster is has to spin to stabilize.  To get heavier/longer bullets to spin fast enough usually requires keeping their velocity up, sometimes faster than lighter/shorter bullets.   The bullet also has to engage the rifling without slipping. 

The rifle shoots very accurately with that Speer JHP.  So there isn't a fatal flaw in it that makes it completely inaccurate.   

What distance were your targets?

[JeffinTD]

I was just at 25 yards.

I was thinking it would be interesting to see what it will do with 158 jacketed billets at the same velocity.

I'll also have to try some 115 grain cast and see how it likes those.

[Litl Red]

New Winchester 1873???   

Here is another one giving about the same accuracy you are experiencing.

Jacketed might deal with a scratched barrel better than cast, something you may be seeing.

http://www.cascity.com/forumhall/index.php/topic,52729.0.html

[JeffinTD]

Wow.

Thanks for posting that.

I wondered about that (an issue in the rifling enough to tear up cast bullets).

I found a review on there rifles somewhere where the author was shooting very small groups with 158gr cast, which my gun clearly won't do.

I'll still try some 125 grain cast, but if that doesn't work...

I was going to order a Marbles peep, but I fink is better wait in case Winchester were to end up keeping the thing, as they did in the thread you posted.

[JeffinTD]

I posted on another 1873 thread, but wanted to post an update here too.

I went out shooting with a friend yesterday who had some 125 grain cast bullets loaded in 38 special brass.  I shot a group in my rifle, and it seemed to shoot pretty good.  He also let me fire his 66, and my 158 RNFP Rimrock bullet with Trailboss in 357 brass seemed to shoot pretty poorly.

When I got home, as luck would have it, some 125gr Rimrock truncated cone bullets I ordered showed up.  I decided to try them with the same brass and load as a direct comparison.  I was really shocked when I fired them off of a field rest.



The one flier in the 5 shot group on the right I'm sure was me.  It would be interesting to fire this load from a proper bench, especially with a peep sight.

For whatever reason my rifle seems to shoot 158 grain cast RNFP or SWC's into huge groups, IE I can out group it with my handguns.

It seems to do fine with 125 cast bullets...

[cpt dan blodgett]

Interesting.
Yes indeed brass manufactured by different companies will have different internal volumes produce possibly different velocities with a given bullet and powder charge, thus affecting accuracy.  But and this is a large but.
We are not shooting bulls eye competions where number of Xs will determine winning and loosing because all the big dogs can hold the 10 ring.

Practically speaking in the SASS world the minor differences between various brands of brass will not make a difference provided you had the sights pointing somewhere near the center of the target.

Now if we are talking long range with a rifle then the minor variations may make a slight difference in group size

[Modoc]

Something I found when working with all copper bullets for our deer rifles was that a simple change in powder made a HUGE difference.  I was loading for a special hunt and my rifle was giving 5" groups at 100 yds.  My wife's rifle shot them at about 1/2".  Both are Remingtons, both the same caliber and twist.  Changed powder and the first batch which ironically was 0.10 gr off of the other powder and my rifle shot about 0.6+/- ".  WTF? 

You might give Unique or Clays a try and see if you get any different results.  I ended up tailoring our rifle loads for CAS to my wife's rifle because it would only reliably feed 158gr RNFP wheras my '73 feeds and shoots everything well (Taylors).  We use these both for CAS and NRA Cowboy Silhouette, so we have to be able to reach 100 meters with some accuracy.

[JeffinTD]

I tried unique, universal clays, and even 2400 with those bullets and none shot well with the 158 rnfp.

It seems to like the 125 truncated cone bullets well with any powder, and they feed great, so I guess that's what I'll run with.