Improving Ruger 77/357 Performance

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GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
I have been experimenting with increasing the effectivness of the 357 magnum as a deer hunting round in the 77/357. By increasing the throat length with a Manson .358 rifle throat reamer to 3/8", it allows seating the 180gr XTP bullet to the second crimp groove. Thus increasing the powder capacity to the same as when a 158gr XTP is seated to nominal C.O.L.

This allows loading 19gr of Lil-Gun powder with no signs of excessive pressure behind a 180gr XTP bullet with a velocity of 1850 to 1900 fps. The loaded round will not fit in the magazine and must be single loaded but can be followed up with a full magazine of standard spec 357 loads.

I have no doubt that any of the 35 caliber rifle bullets of 180 - 200 grains could be used but may not expand as well as the 180gr XTP. ------------- GeezerD
 

robertkirksey

Blackhawk
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Sep 12, 2006
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637
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Alabama
Will a 44 magazine fit the rifle? If so, you could rechamber for some 357/44 wildcat. Might require a little boltface and feeding work but for a little bit of money you could almost equal the .35 Remington in performance.
 

led

Single-Sixer
Joined
Dec 18, 2011
Messages
297
Location
Huntington, WV
Or just rent a 357 Max reamer and have at it. If you're already longer than magazine length why not. In fact, I might need to try this.

Later,
Stephen
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
I don't want to do anything that lessens the versatility of the 357 magnum chambering or ability to use factory ammunition. The long throated 357 magnum should be able to nearly equal the 357 Maximum with handloads adding to the versatility of the 357 magnum chambering.

I thought about reaming the chamber to 357 Maximum and single loading it but the empty case can't be ejected without removing the magazine and I like the ability to have a repeater even if the next shot is less powerful. --------------- GeezerD
 

Jimbo357mag

Hawkeye
Joined
Feb 22, 2007
Messages
10,201
Location
So. Florida
I shoot that 180gr XTP loaded to the second groove in my Winchester AE rifle without any problem. When I checked the throat on the rifle there was plenty of room. I can also shoot the Speer 180gr 35 caliber bullet. I don't hunt but enjoy experimenting a little.

http://www.midwayusa.com/product/545716/speer-hot-cor-bullets-35-caliber-358-diameter-180-grain-flat-nose-box-of-100
 

JStacy

Blackhawk
Joined
May 6, 2016
Messages
503
Location
south Texas
Geezer 1850-1900 with 180 XTP? Is that chronographed or estimate? No insult intended but that is about the same I get from my 357 Max rifle with 22" barrel ? You might want to try some 360 Dan Wesson brass if the loads will fit in your gun.
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
JStacy said:
Geezer 1850-1900 with 180 XTP? Is that chronographed or estimate? No insult intended but that is about the same I get from my 357 Max rifle with 22" barrel ? You might want to try some 360 Dan Wesson brass if the loads will fit in your gun.


It is an estimate. By seating the bullet out as far as possible, it has nearly the same powder capacity as the 357 Maximum loaded to standard specs. And by using Lil-Gun powder with it's lower pressure curve, I don't think that estimate is too far off.

I have no signs of excessive pressure with 19gr of Lil-Gun and have enough room for 21gr. Once I work up an accurate load, I will cronograph the load to see what the velocity is from my 18.5 inch barrel.

Either way, the performance should be much greater than 357 magnum factory loads. ---------- GeezerD
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
Yesterday I went to the range to try some 357 maximum equivalent loads in this 77/357 rifle. Using a 180gr Hornady XTP loaded to a COL of 1.890 in front of 21gr of Lil-Gun in a Remington 357 magnum case with a CCI small rifle magnum primer, there were no signs of excessive pressure.

At 50yds using an aperature rear sight, it will group well inside of 2 inches. 8) --------------- GeezerD
 

JStacy

Blackhawk
Joined
May 6, 2016
Messages
503
Location
south Texas
Geez , thanks for your reply. I will watch for your chronographed loads. Most 357 Mag chambers are long , usually around 1.450 in Contenders and the load out trick sounds promising. Thanks Jim.
Friend and I used to take 357 Max brass and trim it to 1.42 and load the 180XTP with loads like you describe. They were deadly on white tails less than 100 yards.
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
JStacy said:
Geez , thanks for your reply. I will watch for your chronographed loads. Most 357 Mag chambers are long , usually around 1.450 in Contenders and the load out trick sounds promising. Thanks Jim.
Friend and I used to take 357 Max brass and trim it to 1.42 and load the 180XTP with loads like you describe. They were deadly on white tails less than 100 yards.


The throat in my 77/357 was very short. The 180gr XTP loaded to the second crimp groove, would not chamber. I used a Manson .358 rifle throating reamer that cuts a .358 dia. throat to lengthen it to .400 in front of the chamber.

I have also loaded some Sierra 200gr Pro-Hunter bullets but, I doubt if they can be driven fast enough to insure expansion. I also intend to try some Speer 180gr sp rifle bullets.

Looking back, all deer that I have taken in southern Michigan were well inside of 75yds. So the 180 XTPs should work very well. The 158gr XTP soft point bullet driven at 357 max velocities would also be a good load. ------- GeezerD
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
The only loads I put through it prior to throating it were 158gr XTPs HP ahead of 18gr of Lil-Gun. They would group 1 1/2 to 2 inches @ 50yds using aperature sights with an average velocity of 1830 fps. The accuracy with the heavy 180gr loads is about the same after throating. I am going to try 158gr XTP SP bullets seated out with 21gr of Lil-Gun.

So far, everything that I have fired in it is accurate enough for deer hunting. ----------- GeezerD
 

JStacy

Blackhawk
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May 6, 2016
Messages
503
Location
south Texas
I would think the 140 flex tips should have good potential as hunting bullets for small deer and varmints but I just have not worked with them much. Geez have you tried those ? I also agree on the 158XTP SP, completely different bullet than the 158XTP HP, they will stand a lot higher velocity with out blowing up on game.
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
After reading many comments online about the 77/357, it seems that the general opinion is that they prefer heavier bullets. So I have not tried anything lighter than 158gr.

I believe the 140gr flex-tip bullet was developed to improve ballistics in lever action rifles without causing problems in a tube magazine. The 357 magnum is a 100-150yd deer cartridge at best, so I am not worried too much about having the flatest trajectory possible. I think the 158 to 180gr XTPs driven at 357 maximum velocities should stoot flat enough. ------------------- GeezerD
 

ChiefTJS

Blackhawk
Joined
Dec 21, 2011
Messages
819
Location
Nebraska
All I've shot has been 180gr lead with 2400 and I'm pretty pleased. I do intend to try out some other loads but just haven't had the time.
 

GeezerD

Bearcat
Joined
Jan 4, 2017
Messages
26
Location
Southern Michigan
Today I did some shooting with my 77/357 using Lil-Gun powder. The temperature is 90+ degrees with high humidity so high pressure loads are more likely to show indicators of excessive pressure.

Load 1 - 158gr XTP, Sig brass, Win SPM primer, 20gr Lil-Gun, 1.650 COL - No Excess Pressure Signs

Load 2 - 180gr XTP, Sig brass, Win SPM primer, 18gr Lil-Gun, 1.720 COL - No Excess Pressure Signs

Load 3 - 200gr RN Sierra Pro Hunter .358 dia., Win SPM primer, 17gr Lil-Gun, 1.870 COL - No Excess Pressure Signs

These loads were fired in my 77/357 which has a cylindrical throat that is .358 dia. and is .450 in length. All loads are well in excess of Hodgdon data. Load 3 is 2gr more than the maximum load suggested for 180gr XTP but uses a 200gr bullet that is .358 in diameter.

Now I need to chronograph these loads and do some accuracy testing. ----------- GeezerD
 

Jimbo357mag

Hawkeye
Joined
Feb 22, 2007
Messages
10,201
Location
So. Florida
Well that is really pushing it. Glad you got a strong gun. Just because there is no pressure signs doesn't mean you are not over max pressure for the cartridge. I like to stay within the limits SAAMI has established.

http://saami.org/
 
Joined
Oct 26, 2006
Messages
9,479
Location
Woodbury, Tn
GeezerD said:
Today I did some shooting with my 77/357 using Lil-Gun powder. The temperature is 90+ degrees with high humidity so high pressure loads are more likely to show indicators of excessive pressure.

Load 1 - 158gr XTP, Sig brass, Win SPM primer, 20gr Lil-Gun, 1.650 COL - No Excess Pressure Signs

Load 2 - 180gr XTP, Sig brass, Win SPM primer, 18gr Lil-Gun, 1.720 COL - No Excess Pressure Signs

Load 3 - 200gr RN Sierra Pro Hunter .358 dia., Win SPM primer, 17gr Lil-Gun, 1.870 COL - No Excess Pressure Signs

These loads were fired in my 77/357 which has a cylindrical throat that is .358 dia. and is .450 in length. All loads are well in excess of Hodgdon data. Load 3 is 2gr more than the maximum load suggested for 180gr XTP but uses a 200gr bullet that is .358 in diameter.

Now I need to chronograph these loads and do some accuracy testing. ----------- GeezerD
It bothers me that you are over max with your powder charge, and aren't using a chronograph. You may find the only indication you get of overpressue will be BOOM!
http://www.rugerforum.com/phpBB3/viewtopic.php?f=11&t=239550
Good luck.
gramps
 

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