Stainless vs carbon steel barrel heating

[CoalTrain49]

I have a Ruger 77/357 that heats up pretty fast. The barrel is stainless steel. I see considerable lose of accuracy after about 10 rounds. I've tried different loads, jacketed bullets, coated lead bullets, different weights, and different loads. Nothing helps. When the barrel is cold it's a 2 moa rifle, but with a warm barrel it gets pretty wild.

Is it the stainless steel barrel?

 

[Bart B.]

It's not the barrel. Both chrome moly and stainless types will shoot well under MOA through 1000 yards for several dozen shots fired once every 20 to 30 seconds. When made and installed right.

Most common cause for shot stringing as barrels get hot is a poor fit of barrel to receiver. If the receiver face is not square to its barrel tenon thread axis, it's high point bears hard at some point around the barrel shoulder. As parts heat up and expand, the stress at that point makes the barrel whip more in that direction.

Having the receiver face squared up then shimmed so the barrel clocks back into headspace usually corrects the problem. If it doesn't, then the barrel is not stress relieved correctly.

 

[CoalTrain49]

Thanks. I guess I have a gun built on Friday.

That was my first Ruger, may be my last.

I don't have that problem with my CZ.

 

[Bart B.]

Ruger sent twenty of their best custom rifles to the 1992 USA Palma Team for long range matches. Worst parts fit and assembly of any commercial match rifle I've seen. The were dubbed "wash tub" rifles based on their 20-shot test groups at long range. No surprise after learning their barrels were made by Green Mountain.

 

[JRadice45]

The quick heating probably has something to do with the fact that it is a sporter weight barrel.

 

[Offfhand]

Posted above:
"Ruger sent twenty of their best custom rifles to the 1992 USA Palma Team for long range matches. Worst parts fit and assembly of any commercial match rifle I've seen. The were dubbed "wash tub" rifles based on their 20-shot test groups at long range. No surprise after learning their barrels were made by Green Mountain."
Before being too misled by rumors about Ruger’s Palma rifles, there are a few facts to consider: First of all, these were not “commercial” target rifles, but specially designed and built by Ruger for the US Palma team. They were donated to the team by Bill Ruger, with gun cases and other accessories donated by Blount Industries. A couple know-it-alls on the team condemned the rifles even before they were fairly tested. (Much ego was involved here.) As a result, some of the factory fitted barrels were replaced by custom barrels personally favored by some team members. (Ego again.) Poor overall performances were blamed on the Ruger rifles but one fact that still stands out and often commented on, is that the best score fired by a US Team Member was fired with an UNALTERED Ruger rifle. So go figure.

 

[Bart B.]

I was at that 1992 Palma Match and here's what I saw happen.

The USA Team got those Rugers when they showed up the Whittington Center range near Raton, NM. They tested all of them with ammo I and a few others worked up the load for with Sierra's then new 155-gr. Palma bullet the year before. Some Rugers had 6 groove barrels and tested worst; those with 4 groove barrels did better but would still not hold the 20" 10-ring consistently as tested by everyone. Their 3.7 pound triggers were not consistent and didn't break clean at all. Stock design had too low of a comb and the grip was a poor design for prone shooting. Nobody rebarreled any of those rifles issued to them before shooting the big team match.

Everyone on the team shot their own rifles save one whose personal rifle went south; Mike Pelis used the best shooting Ruger in the team match and he did not shoot the high score on the USA team; half a dozen or so shot better scores than he with that Ruger. A friend (bless his departed soul)whose own rifle went south borrowed my Palma rifle and shot a better score than Mike Pelis did, as I remember. All the team member's personal rifles teste sub MOA at 1000 with that ammo as proved the year before when it was used in the Rocky Mountain Palma Matches over 5 days of long range matches. The wind on Team day was not good so comparing scores across the team members is worthless until you pair each one up with his coach giving wind corrections. Four coaches were on the firing line each doping for 4 shooters.

 

[taliv]

i like history as much as the next guy, but it would be a mistake to think that anything ruger did 25 years ago has much bearing on their rifles today. also, different models are designed to different requirements.

 

[Bart B.]

How many Rugers shoot winning scores in F-class or any other long range matches on NRA bullseye targets these days?

 

[Llama Bob]

Posted above:
"Ruger sent twenty of their best custom rifles to the 1992 USA Palma Team for long range matches. Worst parts fit and assembly of any commercial match rifle I've seen. The were dubbed "wash tub" rifles based on their 20-shot test groups at long range. No surprise after learning their barrels were made by Green Mountain."
Before being too misled by rumors about Ruger’s Palma rifles, there are a few facts to consider: First of all, these were not “commercial” target rifles, but specially designed and built by Ruger for the US Palma team. They were donated to the team by Bill Ruger, with gun cases and other accessories donated by Blount Industries. A couple know-it-alls on the team condemned the rifles even before they were fairly tested. (Much ego was involved here.) As a result, some of the factory fitted barrels were replaced by custom barrels personally favored by some team members. (Ego again.) Poor overall performances were blamed on the Ruger rifles but one fact that still stands out and often commented on, is that the best score fired by a US Team Member was fired with an UNALTERED Ruger rifle. So go figure.

I believe this is exactly correct, and one of the egos in question is at work in another post

 

[taliv]

you know the rifle in the OP is chambered in 357, right?

I'm sure you know that people win matches, not guns. So your question has very limited relevance until the people who are capable of winning matches start shooting rugers.

Savage did a great job of breaking out of their old reputation a few years ago by getting good shooters to shoot stock savages and win some matches. I suspect ruger could do the same, except their Ruger Precision Rifle (not chambered in 357) is more oriented towards the PRS style of shooting. Palma may be a better test of a rifle's accuracy, but it's so friggin boring, I can't blame Ruger for not spending much time there.

In any event, I have personally witnessed a couple of RPRs that shoot tight enough to win (and a couple that were 1 MOA or worse)

 

[Llama Bob]

As far as OP's problem, quite frequently pistol caliber rifles are loaded with ammo that, uh, isn't exactly match quality. You know, pistol ammo.

Has an effort been made to load match ammo for the rifle, before criticizing it's accuracy?

 

[351 WINCHESTER]

Never had a Ruger rifle that would shoot.

 

[AlfonsDeWolf]

More friction in s.s causing heat causing your problems? Try a hardcast .357 maybe.

 

[jmr40]

Ruger bolt guns are generally more than accurate enough for most hunting. The newer American action is an improvement over the old 77 actions far as accuracy is concerned.

The old rifles with non Ruger made barrels were all over the place. Some decent. Some horrible. But sometime in the early 90s Ruger started making their own. Much more consistent. But rarely match grade. But that is ok. The ops rifle is a hunting rifle. I wouldn't expect match grade accuracy

 

[CoalTrain49]

The rifle would be fine for hunting.

I'm just used to rifles that shoot a little better with warm barrels.

Gil Horman writing for American Rifleman found the rifle to be 2 moa with factory loads. If a person shoots 5 rounds and lets the barrel cool for a few minutes there isn't a problem, it's a 2 moa rifle.

It's a fun little carbine and would make a pretty good brush gun. I think I might have been expecting a little too much from a PCC.

 

[RecoilRob]

If the action is held in the stock the same way the 77 rifle is done, my 223 Target was VERY sensitive to the torque and procedure of torquing the screws for it to shoot accurately. The front screw pulled the action back against a wedge-like block and was the first to be torqued down, then the rearmost trigger guard screw with the middle screw being very lightly pulled in only.

I just looked up the torque values and came up with 65 in/lbs on the front screw which is the only important one where the rear one is maybe half that and middle one just snug. Been a while since I've had the rifle, but man...it shot well, enough so that a fellow at the range who saw it talked me out of it. He was happy...for a while, then called one day complaining that the rifle suddenly stopped shooting!

After a little chat it became obvious that he'd had the action out of the stock and had messed up the tensioning so we had to go over that again and this returned the accuracy it always delivered. Could the 357 be sensitive to this same phenomenon? Sure wouldn't hurt to give it a try.

With all screws loose, gently snug up the front screw...then bump the stock down against the floor firmly a couple times to seat the lug, then torque the front screw down. Then pull the rear guard screw down and then lightly seat the middle one. Give it a try. Can't make it worse!

Might also check to see how the barrel is tensioned in/by the stock. Some of the synthetic stocks aren't as stable as they could/should be and if there is tension being applied to the forward point it might be changing as the barrel heats up. If there IS contact, varying this point or even eliminating it with free-floating might show improvements. I agree that MOA isn't normally needed on a pistol caliber carbine, but it would be nice for it to remain consistent as it's being fired.

 

[Walkalong]

I have a Ruger 77/357[/B] ......................I see considerable lose of accuracy after about 10 rounds. I've tried different loads, .............................. Nothing helps. When the barrel is cold it's a 2 moa rifle, but with a warm barrel it gets pretty wild.

Is it the stainless steel barrel?

I doubt it. It's just a thin barrel that gets hot.

 

[M1key]

I wouldn't think the M77 357 was designed for longer shot strings. It's a lightweight hunting rifle that scoped will shoot three to five shots into 2 MOA. Why would you expect anything more?

M

 

[CoalTrain49]

I wouldn't think the M77 357 was designed for longer shot strings. It's a lightweight hunting rifle that scoped will shoot three to five shots into 2 MOA. Why would you expect anything more?

Probably I just don't have enough experience with LW barrels. This seems to be the case here. Glad I ask the question, I found the answer.