M77 357 Mag

[mg2112]

All

I recently picked up an M77 chambered in .357, and it’s a really cool little rifle that I’m very happy with. My best group at 100 yards so far has been 3.5 inches—not bad, but I think it can do better. My sample size is small with only about 70 rounds shot.

So far, I’ve shot:

.357 PMC 158 Grain JSP
.357 Winchester SuperX 158 Grain JSP, using a Bushnell 1.5-4.5 scope.

With both loads, my best group at 100 yards is 3.5 inches, while at 50 yards the holes are touching. I’m curious what, in your experience, is the best shooting ammo for this great rifle.

 

[WAYNO]

These are not known for being accurate, however there have been exceptions, including one in .44 that I owned at one time.
I've owned quite a few in both .357 and .44, and I was mostly disappointed with them.

I have discovered that there are huge accuracy differences between different loads. In my last .357, the Hornady Leverevolution round was vastly superior to any other load in this rifle.

 

[mg2112]

These are not known for being accurate, however there have been exceptions, including one in .44 that I owned at one time.
I've owned quite a few in both .357 and .44, and I was mostly disappointed with them.

I have discovered that there are huge accuracy differences between different loads. In my last .357, the Hornady Leverevolution round was vastly superior to any other load in this rifle.

I will try that ammo. Thanks

 

[Air-cooled]

My Deerfield semi-auto .44mag is is about the same accuracy.

 

[kmoore]

I would try 180 gr jacketed bullets. Hornady makes them, even has loading data for .357 in rifles.

 

[Klondike Mike]

I don't know if this will help but I have a Marlin 357 that shoots best with Hornady 140 grain XTP's in my hand loads. They're probably worth a try in your 77/357. Good luck and have fun tracking down its favorite load.

 

[azleite]

I don't know if this will help but I have a Marlin 357 that shoots best with Hornady 140 grain XTP's in my hand loads. They're probably worth a try in your 77/357. Good luck and have fun tracking down its favorite load.

What powder are you using?

 

[Klondike Mike]

Good old 2400.

 

[mg2112]

testing continues. The Winchester SuperX 158 Grain JSP continues to shoot well. A nice 3 inch group. I got some blazer 158 grain JSP and it shot well. see attached files. Silhouette target is a 9 shot group with the blazer. bullseye targets (left) blazer, right Winchester. more ammo on the way. testing will continue.

 

[s4s4u]

The trouble with the 357, as well as other pistol calibers, are bullets with crappy BC's. Short and fat doesn't relate to downrange consistency and accuracy. Find a bullet with a respectable BC, and you may be able to tighten it up a bit, but 3.5 moa is quite respectable @ 100 yards.

 

[Mobuck]

Consider that 'most' 357 ammo is designed for handgun use and long range accuracy is NOT a high priority.
Honestly, 3MOA is pretty darned good.

 

[375hh1973]

Consider shimming the bolt.

Did that to my 77/44 and 77/22mag and it helped in both instances

 

[protoolman]

Well if I was going for accuracy I'd get into long cast bullets maybe with gas checks and a round nose or maybe even spire tip. Not sure what's available however.

 

[rugnelli]

I don't know about the best accuracy, but my Daughter shot several deer with 140 grain FTX LeverEvolution. It grouped better than 3.5" at 100 yds for her.

 

[kmoore]

When I said try the 180gr, I said that because the normal bullets for that are shaped like a soup can. The 180s may do better with more bullet griping the barrel. But The LeverEvolutions with their pointy bullet shape would be worth trying.
I loaded a box of LeverEvolutions in my 45-70. Thinking they were 300 gr. The 405 gr flatnose bullets shoot much smaller groups. So, I passed on them.

 

[M118LR]

Every rifle will choose its own favorite load. Seems you keep trying to force feed it 158 grains, and it isn't responding to your wishes. If your not reloading select a box of every different projectile weight and design until the rifle tells you what it prefers. Then you can begin to purchase the projectile it prefers until you find the load with the specific powder that works best for its preferred projectile. When reloading you can simply craft 5 of each until you find the specific node that gets you close enough to tailor the load for optimum performance. Of course you will still keep experimenting just in case a new powder or projectile can make Old Betsy perform a hair better, or perhaps just as well for a penny a round less expensive. JMHO YMMV.
Edit, Lee used to make hand loading kits for straight walled cartridges like the .357 which allows for entry level hand loading at a minimal cost, and they fit in a coat pocket so they can travel everywhere. Of course the size of the rubber mallet is that of the crafters choice.

 

[mg2112]

Testing is complete.

The Hornady 140 grain FTX produced a 3.2-inch group at 100 yards, excellent and consistent.
The Winchester 158 grain JSP had a 3.7-inch group at 100 yards, very consistent.
The Remington CoreLokt 180 grain also grouped at 3.7 inches at 100 yards.
The Remington HTP 158 grain SJHP had a 3.0-inch group; overall it shot poorly, but there was one really good group.
Minimum 3 shot groups; 4 separate targets.
I’m pleased with the results and enjoy shooting the rifle. It has more than enough accuracy for deer and bear hunting this fall in Maine.

A couple of pictures attached. The square white steel is at 200 yards, with 5 shots all hitting using a 1x4.5 scope. No adjustments were made; I just held the reticle on top of the target. I used Winchester 158 grain JSP.

Paper target is 9 shots off hand at 50 yards using the Winchester ammo.

 

[M118LR]

Have you tried other 140 grain loads to see if the shorter lighter projectiles will have less than two inch 3 shot groups, or is the Hornady 140 FTX load good enough for your purpose?

 

[Pauerpilot]

I have a 77/357 stainless. Out of the box it is fun to shoot. I did some modifications to my rifle. I put in a Timney trigger. Well worth the time and effort. I put on a good glass 1-4 power scope. I hand load 140gr FTX using H110. I am pushing the bullets to ~2050fps. It's hot but the rifle is good to go. I have not had any high pressure signs. So far this rifle has taken Mule deer and whole lot of hogs. It is my go to hog rifle. I sight in the rifle at 50 yards. My shots are rarely over 100 yards. At 50 yards, I am getting very close to MOA maybe a bit larger than that. However, this is not a match rifle. At 100 yards I would say 2-3 MOA is reasonable. I noticed a difference with the trigger. Not a massive difference but it sure is better than the stock trigger. I would say if you hand load for this rifle, keep the ammo dedicated for the rifle and not shoot that ammo in any handguns. The 77/357 is a stout action. In a handgun it is not fun to shoot those full power loads. The rifle is very capable and the caliber is packs a punch. Do not under estimate the combination. Do your due diligence and the rifle will put sizable animals down. I just shot a 340lbs. hog earlier this year. One shot and the boar was down. Hope this helps.

 

[mg2112]

Have you tried other 140 grain loads to see if the shorter lighter projectiles will have less than two inch 3 shot groups, or is the Hornady 140 FTX load good enough for your purpose?

the 140 ftx shot the best group, was point of aim/point of impact. I am looking for 125 JHP to test out.

 

[mg2112]

I have a 77/357 stainless. Out of the box it is fun to shoot. I did some modifications to my rifle. I put in a Timney trigger. Well worth the time and effort. I put on a good glass 1-4 power scope. I hand load 140gr FTX using H110. I am pushing the bullets to ~2050fps. It's hot but the rifle is good to go. I have not had any high pressure signs. So far this rifle has taken Mule deer and whole lot of hogs. It is my go to hog rifle. I sight in the rifle at 50 yards. My shots are rarely over 100 yards. At 50 yards, I am getting very close to MOA maybe a bit larger than that. However, this is not a match rifle. At 100 yards I would say 2-3 MOA is reasonable. I noticed a difference with the trigger. Not a massive difference but it sure is better than the stock trigger. I would say if you hand load for this rifle, keep the ammo dedicated for the rifle and not shoot that ammo in any handguns. The 77/357 is a stout action. In a handgun it is not fun to shoot those full power loads. The rifle is very capable and the caliber is packs a punch. Do not under estimate the combination. Do your due diligence and the rifle will put sizable animals down. I just shot a 340lbs. hog earlier this year. One shot and the boar was down. Hope this helps.

A mule deer—that’s awesome. I’ll try some lighter loads (125/140) to check accuracy. I wouldn’t go beyond 100 yards, but I like knowing my limitations. It’s a fun little rifle—light, handy, and easy on the eyes. Thanks for the post.

 

[mg2112]

The Winchester SuperX 158 Grain JSP remains a consistent round, delivering a 3-inch group at 100 yards as always.

 

[mg2112]

The Winchester 110-grain JHP performs well at 50 yards, as shown below, but at 100 yards it opens up to about 4 to 6 inches.

 

[mg2112]

I think its Buffalo Boar for the win.

Targets marked as follows:
HC = HEAVY 357 MAG OUTDOORSMAN 180 gr. Hard Cast LFN-GC
JHP = BUFFALO BORE HEAVY 357 MAG 180 gr. JHP

JHP achieved two-inch groups at 100 yards, and close to the point of aim.
HC produced one two-inch group and one three-inch group at 100 yards, again close to point of aim.

Very happy with the results.

 

[kmoore]

I think its Buffalo Boar for the win.

Targets marked as follows:
HC = HEAVY 357 MAG OUTDOORSMAN 180 gr. Hard Cast LFN-GC
JHP = BUFFALO BORE HEAVY 357 MAG 180 gr. JHP

JHP achieved two-inch groups at 100 yards, and close to the point of aim.
HC produced one two-inch group and one three-inch group at 100 yards, again close to point of aim.

Very happy with the results.
View attachment 107674View attachment 107676

Good shooting, the rifle/shooter is doing well. It seems that most loads did good with your tests. I never did bench testing with my win 92 rifle in 357. I found the 180s where hitting clay targets at 50 yds more so than 125s and 158s. Its fairly easy to hit 10 steel plate at 100yd standing using the 180s. To be honest, a 10 steel plate would likely catch any of those loads.