G2 carbine accuracy (or lack thereof)

[mrmoore2]

Greetings! It’s been a while since I posted anything, but I’ve run across a situation that has me buffaloed so I thought I would toss it out to see if the collective wisdom could shed some light on it.

I have a G2 Contender with a 16” 357 magnum barrel from the T/C Custom Shop. I’ve had it for a couple of years and always shot the 204-grain Lyman 358315 and have been happy enough with it. It’s no varmint gun, but it certainly shoots minute-of-pig or better. Recently I tried some Lee C358-158-SWCs in an effort to find a lighter, quieter load for use at my new 50-yard backyard range. Much to my surprise, instead of the nice little(-ish) groups I get with the 204s, I had a hard time keeping the 158s on the 12” x 18” piece of plywood that I hung the target on. One five-shot pattern measured over 17” (off sandbags at 50 yards!). At first I thought I had leaded the barrel up, but that wasn’t it. I made the Lee 158s, so it may be operator error on those but that doesn’t explain the rest of them.

Since then I’ve tried a variety of other bullets from 125 to 220 grains, jacketed, plated, and cast with several different powders. None were as wild as the Lees, but they are all pretty bad, with the exception of some plated 158 grain FPs that shoot a little better than the Lymans.

The Lees shoot much worse than anything else, but several of the others have thrown 5-6” patterns so I don’t think it’s all in the bullet. I tried a different scope, no change. I’m thinking about ditching the “custom shop” unit and ordering a new one from MGM, but before I do anything that drastic I’d like to hear some other thoughts on the subject. Any suggestions on how to whip this thing into shape?

Many thanks from Waxahachie Texas,
Randy

[Artful]

What twist rate is you barrel? And you said you tried 220 jacketed and had poor accuracy with them, is that correct?

[Frank46]

Rather than treating the G2 like a carbine. try setting your bullets out like you would a rifle. Heard something similar regarding some cadet martinis chambered in 357 mag. Do not use a heavy crimp like you would use on pistol ammo. Seat the bullets out to engage the rifling and heavier powder charges since your bullet is seated out further. And find out what typw reamer was used to ream the chamber of your rifle. They may have used a pistol reamer instead a rifle reamer they are different. Frank

[runfiverun]

look at your throat.
you could probably seat those 200 gr boolits out further.

[stubshaft]

+1 - On seating your boolits out. You've probably got a very long throat, which is not a real surprise with T/C.

[mrmoore2]

I believe this barrell is a 1:14 twist. I did try some 220 grain JSPs and accuracy was similar to the 204s.

Y'all are all correct about the long throat, so far I have not seated a boolit that will reach the rifling. I think I'd have to crimp it on the gas check to make that happen.

I just keep thinking that a defect serious enough to make one shoot that wild would be obvious. It may well be that I just don't understand what I'm looking at.

Randy

[Nobade]

It's not a defect, it's the standard SAAMI throat for the 357. Long tapered cone throat like a 458 win mag. Boolits as big as will fit in unsized fired cases, seated out to touch the throat, will work. Ranch Dog 175gr. has a really fat nose and is designed to solve this problem. It's the only boolit that will shoot in my 357 carbines and still feed through the action. Paper patching rifle boolits also works well, see my recent post in the paper patch smokeless room re: patching for a contender.

[Moonie]

Lots of people have these barrels rechambered to 357 Max to fix the long throat issue, that normally fixes it (assuming the rechamber job uses a proper throat).

[35remington]

Go to Mike Bellm's Contender site and see what he has to say about T/C chambers in 357 magnum. The throats these guns have give him fits of hyper gagging, and his best and excellent advice is to recut the throat and rechamber to 357 maximum. This gives a power and accuracy boost at the same time.

The throats really are utterly horrible in 357, with a super long length and, worse yet, a taper. I consider it a defect, and darn near a crime to cut a single shot pistol barrel this way. It's okay for a revolver.......not a single shot. Good luck getting any but the heavy long bullets to touch the rifling (forget about "touching the throat" as Mike explains that this is not particularly helpful). Unless they're 200 plus grains and have a whole bunch of bearing surface and a short nose, they ain't gonna touch the rifling while the bullet's still in the case. And he also points out that seating even a long heavy bullet to touch the rifling does not help the rear of the bullet start straight because the throat is tapered.

Not good.

Scroll down until you see the first color photograph in the link below. It's a picture of a typical TC 357 magnum throat. It's hideous.

http://www.bellmtcs.com/store/index.php?cid=120

You can wrestle with it for awhile, but it's a myth that a gun can be made to shoot as well as possible even if the throat is bad.

It simply cannot and will not shoot up to its potential until poor dimensions are addressed. You can apply any cast bullet voodoo you want......ain't gonna help as much as it could have. Unless you do something about the throat.

I am the unfortunate victim of TC throats in several calibers. Found out the hard way myself.

[paul h]

Yup, 357 mag contentenders have horrible "toilet bowl" throats. I had a 10" 357 mag contender barrel, and I could literally seat a 200 gr wfn cast bullet with only the gas check seated in the case, and still not hit the lands! 357 mag contender barrels are notorious for poor accuracy.

[williamwaco]

Well,

I have the 12" G2 barrel in .357 mag. I have no trouble at all getting 2" at 50 yards. With the Lee T358-158-SWC cast soft and sized .358 at any velocity from 900 to 1400. The same bullet cast hard and sized .356 was a DISASTER.

I seat to crimp in the top lube groove.

It also does well with the Lee C357-158-RF t 25 yd. I have not had the opportunity to try that bullet at 50 yd.




.

[mrmoore2]

Thanks for all the input. I went out to the shop earlier to see if it would be possible to seat a boolit long enough to reach the rifling in this barrel. According to my rough measurements, it's .495" from the case mouth to the rifling. I could seat my 158 SWC's on the gas check and they would still be 2/10" shy of the rifling. I see that Accurate Molds has a boolit (36-175D) similar to the Ranch Dog mold that Nobade recommended, I may try that just to see what it will do (not a big fan of TL boolits). Or I may order a replacement barrel from MGM and use this one for a trotline weight. Haven't quite decided yet.

Randy

[leadman]

I had a 10" 357 T/C barrel that liked the boolits sized to .359" or larger. My Marlin lever also liked boolits on the large size.
The best performance in both was with the SEACO 180gr RFN GC. The Lee 158 RFN also did real well in the Marlin. I usually shot this at 1,600 to 1,700 fps in the Marlin.
Both of these boolits are tapered from the crimp groove forward. I think this helps align the boolit in the leade, versus the square shoulder of the SWC.

[Moonie]

Thanks for all the input. I went out to the shop earlier to see if it would be possible to seat a boolit long enough to reach the rifling in this barrel. According to my rough measurements, it's .495" from the case mouth to the rifling. I could seat my 158 SWC's on the gas check and they would still be 2/10" shy of the rifling. I see that Accurate Molds has a boolit (36-175D) similar to the Ranch Dog mold that Nobade recommended, I may try that just to see what it will do (not a big fan of TL boolits). Or I may order a replacement barrel from MGM and use this one for a trotline weight. Haven't quite decided yet.

Randy

If you aren't interested in rechambering please don't do anything rash, some of us would love once again own a contender.

Let me know, I'd love to have the barrel.

[Four-Sixty]

Something I've been wanting to ask about the .357 Maxium is:

If you have one of the new MGM barrels chambered in .357 Maximum, can you shoot .357 Magnum out of it with success? Would it be accurate?

Also, would you cause any errosion to the chamber by using the shorter round?

I want to get into the Maximum, but am put off by the lack of brass.

[kir_kenix]

I have a 10" g2 barrel in .357 mag that is similar to yours. Only shoots moderately well with heavy, looooong boolits. Groups are garbage with anything less than 200 grains and a mile of bearing surface.

T/C is aware of the problem and does not care.

I will eventually ream mine out to .357 max and solve the problem once and for all.

[Nobade]

35 Remington Rimmed (make from 303 Brit brass or 30-40 Krag) works really well for rechambering these barrels. Either more power than a Herrett, or the same power at lower pressure.

But I tell ya, load the 357 right with boolits that fit properly and they will shoot. It's the same situation as the 458 win mag - normal boolits won't work, you need to come up with what fits YOUR individual chamber. But when you get it right it really works well.

[Dthunter]

I got a 21" 357Max barrel for my G1 contender. The throat is so long that I can drop a 220 grain semiwadcutter cast bullet in front of the case and chamber it without the bullet touching the case!
I have over an inch of nothing in front of the chamber. Its pathetic! Never seen such bad judgement by a manufacturer to chamber this way! Shoots like "you know what"! I have tried everything imagineable to get It too shoot!
In the end, I just got two new barrels in different calibers!
They are much better!

My 6TCU barrel shoots 87grain hornady HPBT bullets at 2800fps and into .5-.75" at 100 yds! What a Difference!

Getting barrels up here for a G1 contender takes nearly 6 months(or more) to get!
Maybe I should just rechamber the Maximum barrel to 35 Remington. But I think the exsisting throat would still be too far ahead! Lol!

[leadman]

Is the chamber long enough to use the 360 Dan Wesson in it?

I had a 45/410 Contender barrel and used cut down 460 S&W to fill the chamber and it was better, but still not great.

[Nobade]

I got a 21" 357Max barrel for my G1 contender. The throat is so long that I can drop a 220 grain semiwadcutter cast bullet in front of the case and chamber it without the bullet touching the case!
I have over an inch of nothing in front of the chamber.

Do you have any Cerrosafe? A picture of the chamber cast from that barrel would be very educational.

[MT Gianni]

Something I've been wanting to ask about the .357 Maxium is:

If you have one of the new MGM barrels chambered in .357 Maximum, can you shoot .357 Magnum out of it with success? Would it be accurate?

Also, would you cause any errosion to the chamber by using the shorter round?

I want to get into the Maximum, but am put off by the lack of brass.

There is no large lack of brass. It is available but generally seasonally. You can shoot 38 & 357 in them. I have a rechambered Handi in 357 Max. It does it's best work with max's but shoots 357 OK.

[MT Gianni]

Something I've been wanting to ask about the .357 Maxium is: Also, would you cause any errosion to the chamber by using the shorter round?


I think that depending on the powder you might have a measurable corrosion issue in as few as 15,000 rounds.

[Dthunter]

Nobade:

Sorry about the delayed response!
I do have some serrosafe, but it presently is cast into a copy of my 7mm Ultra chamber. I would like to see it! But never the less, it shoots like ****! Good enough for treestand bear baiting, but thats about it! One day it will group into 1.5" at 100, then the next day 3-5"! With the same load. Terribly frustrating!

[Larry Gibson]

What load(s)?

It is very easy, with carbine length barrels, to push cast bullets to hard or to fast, especially PB'd SWCs for good accuracy.

Larry Gibson