22-6mm Extended-Long Range Groundhog

[Trickymissfit]

I think I'd do a 6mm Vias instead of the 6mm Remington case necked down to 22 caliber. First of all it's way overbore, and will probably eat barrels rapidly. A 6mm Vias will push a 70 grain bullet faster than a .220 Swift can push a 50 grain bullet if that matters much. The Vias is simply a 6.5x55 case slightly shortened (about a millimeter), and inproved to something like an Ackley design. There is a 22 Vias as well. By the way a 6mm Vias shooting 70 grain bullets is good for about 4,000fps in a 26" barrel, but really starts to show it stuff with bullets 85 grain and larger. It ought to easilly push a 105 grain Amax to 3300 fps. I shoot a 6/250AI out of a 26" barrel, and it will push a 105 grain Amax to 3100 fps (max). Needs another .075" of neck length, or better yet just ream the chamber with a 6mm Ackley chamber reamer setup for the 250AI headspace. That barrel's gonna last a long time. Of course you can do the samething with that reamer and make it a 6x55AI, and make your cases out of generic 6mm Remington cases. Use a 1:8 twist barrel that's about 26" long

When you start to look at 500 yard + ranges, you want to be thinking about the 6mm bore size anyway, and after 700 yards you need to be looking at the 6.5's
gary

 

[Trickymissfit]

I am using a short action an I know to remove a chambered loaded round I will have to remove the bolt, not a big deal to me.

Thanks, I wasn't sure.

I did some testing, when I first got my short action Savage single shot rifle. A 57mm case length will cycle thru it with no problems (the Savage action is about 5/32" longer than a Remington). Remington did build a few 6mm Remingtons on their short action, but was kinda unhandy with long bullets like the 105 grain Amax. Plus to make them really work well you have to seat the bullets deeper in the case
gary

 

[shortgrass]

Take a look at the 6mm Dasher for a SA round.

 

[Trickymissfit]

Take a look at the 6mm Dasher for a SA round.

before I'd even consider a Dasher (good round with it's own issues), I'd do a 6BG or a .224BG. It's kinda like a stretched 6BR case, and brass is made from .243 generic brass. Case is about two inches long with a neck similar to the 6BR with a thirty degree shoulder. It will push a 105 grain Amax to about 2950 fpswith a barrel life that's gonna last a long, long while.
gary

 

[Hunter2678]

before I'd even consider a Dasher (good round with it's own issues), I'd do a 6BG or a .224BG. It's kinda like a stretched 6BR case, and brass is made from .243 generic brass. Case is about two inches long with a neck similar to the 6BR with a thirty degree shoulder. It will push a 105 grain Amax to about 2950 fpswith a barrel life that's gonna last a long, long while.
gary

Heck why not just go to a 6x47 then...? Lapua brass,105s @ 2950-3050 fps. Just use a bushing die to take it from a 6.5 to a 6mm and boom you're done...no special tricks or steps. Good barrel life too. I know of 7-8 guys shooting them in a large group that shoots 1000 yds regualry around here and they prefer its characteristics & performance at 800+ yds. Many of them have settled on it after trying out many other LR cartridges over the yrs.

 

[Trickymissfit]

Heck why not just go to a 6x47 then...? Lapua brass,105s @ 2950-3050 fps. Just use a bushing die to take it from a 6.5 to a 6mm and boom you're done...no special tricks or steps. Good barrel life too. I know of 7-8 guys shooting them in a large group that shoots 1000 yds regualry around here and they prefer its characteristics & performance at 800+ yds. Many of them have settled on it after trying out many other LR cartridges over the yrs.

The BG is probably the single most efficient 6mm round out there, and is known to group similar to a 6BR, but with much better range and heavier bullet capability. Cases can be made very cheaply, and are really pretty easy to form out of .243 brass. All it really is, is a 6BR with .30" added in the middle. No over priced brass to buy and case life and barrel life are way up there. The easiest one to do is the 6/250AI with the 6mmAckley neck. you end up with a neck length of about .32" and a 40 degree shoulder (2" case length) after shrinkage from fire forming. I form my cases right now out of generic .243 brass that's shortened to about 1.925", but the next batch will be only about .005" shorter than the chamber neck length (about 1.937"). I'm seeing about .030" shrinkage. But I may do my next barrel for a 1.472" headspace and the full 6mmAI neck & shoulders. That way I can use nearly all the .243 brass. Guess it's to each his own.
gary

 

[mikebob]

I have a 22-243 with 1-8 hart shooting 90gr berger vld @ 3350fps. I absolutely love this gun for yote hunting. Its total weight is about 15lbs and it will shoot yote's drt at 1300 yards (farthest i can dial until i get 20moa base). At 800 yards its just shy of 1000ft lbs energy and 2200fps and 0.8mil drift in 10mph wind.

 

[Trickymissfit]

The BG is probably the single most efficient 6mm round out there, and is known to group similar to a 6BR, but with much better range and heavier bullet capability. Cases can be made very cheaply, and are really pretty easy to form out of .243 brass. All it really is, is a 6BR with .30" added in the middle. No over priced brass to buy and case life and barrel life are way up there. The easiest one to do is the 6/250AI with the 6mmAckley neck. you end up with a neck length of about .32" and a 40 degree shoulder (2" case length) after shrinkage from fire forming. I form my cases right now out of generic .243 brass that's shortened to about 1.925", but the next batch will be only about .005" shorter than the chamber neck length (about 1.937"). I'm seeing about .030" shrinkage. But I may do my next barrel for a 1.472" headspace and the full 6mmAI neck & shoulders. That way I can use nearly all the .243 brass. Guess it's to each his own.
gary

I need to make a correction in my post. The BG round is similar to the 6BR, but about .50" longer in the main part of the case body. The neck and shoulders are very similar to the older 6mm HLS. There are two versions of it. One has .0125" of taper per foot, and the other has .0175" of taper per foot. Case headspaces off a .300 Savage head space gauge with max overall length being about 2.020". I found the reamer drawings last night. Cases used were .243 lapua, and it will push a 107 grain Sierra to 2950 fps
gary

 

[shortgrass]

I need to make a correction in my post. The BG round is similar to the 6BR, but about .50" longer in the main part of the case body. The neck and shoulders are very similar to the older 6mm HLS. There are two versions of it. One has .0125" of taper per foot, and the other has .0175" of taper per foot. Case headspaces off a .300 Savage head space gauge with max overall length being about 2.020". I found the reamer drawings last night. Cases used were .243 lapua, and it will push a 107 grain Sierra to 2950 fps
gary

My 6mmXC does the same (2950fps. w/ 107g SMK or 108g. Berger Target),,,,,, and I can buy Norma brass, don't have to make it!

 

[Trickymissfit]

My 6mmXC does the same (2950fps. w/ 107g SMK or 108g. Berger Target),,,,,, and I can buy Norma brass, don't have to make it!

must be very hot!
gary