Enjoyed a cast bullet and Ruger 77/357 morning at the range, but lots to learn...

[Tallbald]

With the help of wonderful people here over the last summer, I jumped into this wonderful hobby of casting. I've posted here that I have found a wonderful light putterbutt load my rifle has been loving, using Trail Boss and the Lee 125 grain round nose flat point bullet. Monday at the range I was pleasantly shooting sub one inch 4 shot groups at 75 yards from a solid rest using a Leupold Rifleman 2-7 scope and bipod off a bench. Light crosswinds and sunny 45 degree temperatures, as well as there just being me and a friend on the range added to the pleasure.
The alloy mix was by weight 7 parts pure lead to 5 parts wheel weights and 2% tin. I tumble lube with Alox. The Lee load manual lists this load as being below 1000 FPS, but I'm thinking that's from a handgun length test barrel. After 35 or so shots, groups began opening up to as big as 1 1/2 inches at which time we had quit to head back to town. I'd like to have had time to clean my barrel and try again, but I'm thinking that with the carbine length barrel, the loads are reaching significantly higher speeds and I will have to switch to a harder alloy. WW aren't easy to find in my area and I was hoping to ration the WW I have (thanks to a very kind and generous member here) but see no other option.
Some members on other forums I've seen complain about factory barrels, and have posted that the 77/357 is at best "minute of deer" and a great "truck gun" for up close critters. I'm no skilled competition rifleman but honestly folks I'm pleased as punch with the almost- MOA groups my beautiful, simple and rugged little carbine gives me with this 6 or so cent a round load....with a clean barrel of course. Greetings to all and as always, thanks for the many kindnesses shown me. Don.

[robg]

with no cylinder gap longer barrel you proably get an extra 200fps in a rifle.only way to be sure is to use a chrony

[petroid]

You should be able to water quench or hear treat that alloy to a harder bhn if you so desire but I'm not sure it's necessary. I shoot 50/50 pure/coww up to 1800 fps in 300BLK with similar accuracy. Weight sorting your boolits may tighten those groups back up

[44man]

I did real good with 50-50 by oven hardening after sizing.

[Foto Joe]

I guess the simplest way to effect an accuracy cure would be to harden up your boolits by water dropping but that might not be the issue. I'm a big fan of LLA tumble lube or even better 45/45/10 tumble lube but you might be a little short on lubrication in a rifle barrel at high velocities with either. It would be interesting to know if you're getting any leading and if so where? i.e. full bore, breach end or muzzle end of the barrel. If your accuracy is headed down hill after a couple of dozen rounds I'd suspect that you're getting some leading somewhere and enough to make a difference in where the boolit lands from the looks of it.

[FredBuddy]

...........and then, there's powder coating.

[joesig]

I agree with Foto Joe. Where is the leading, near the chamber or near the muzzle? That will tell you if it's hardness or lube. Considering how well your loads started out, my guess is lube and lead near the muzzle.

[petroid]

I didn't see where the OP indicated there was leading.

[MT Chambers]

Is that a gc design? If so, did you use a check? If it's not a gc design, I'd get one for use on the .357 at higher velocities. This was proven many many years ago in .357 factory lead loads.

[dubber123]

I'd look at a different lube first. I routinely shoot air cooled, PB WW boolits at about 1,600 fps.with no degradation in accuracy. If your lube is in question, it's not too hard to just hand lube enough for a test, which doesn't require any monetary outlay. I did that a lot when I was just getting started.

[Jeff Michel]

You've reaffirmed what I've been seeing. In spite of the grousing about the 77/357 a lot of people have been doing, mine shoots like a laser with everything I've shoved in it from 105 grain Lee SWC in a special case to max loads of 2400 pushing a Milhec 180 grain HP. Enjoy your rifle, It's one of my favorites.

[altheating]

Same here, mine shoots! Can't comment on light boolits as I have only used NOE's 360-180. One thing I did was to lap the barrel, that made a huge difference in accuracy an have zero leading. Seems like I cAn shoot it all day and clean with a few patches. Glad yours shoots well.