.243 Win. AI vs. 6mm Rem. AI

[dimecovers3]

Could somebody tell me,that knows first hand) what the velocity advantage is of the Rem. over the Win. is on bullet weights from 75 to 100 grains? I want to build a 6mm A.I., but am not sure the velocity claims I read are true over the .243 AI. Is the 700 action in 6mm Remington the "short action"--seems I read once it was not or was, but caused problems with longer bullets. I'm affraid they are, which makes this difficult given the choices in rifles and brass is so much better for the Winchester. Not, that I'd go on brass alone, but I would on factory rifles available. Just can't understand why there is only one crappy Rem rifle chambered in 6mm. I can't go custom. Would like a SS 700 action and would replace stock and barrel as money and need indicated. And and in a related thread on the Pros and Cons of the .280 Rem and .280 AI, is the 6mm AI "worth" the extra trouble over handloaded,and factory if there is a big difference) over the standard Rem. 6mm? I want this to be a lightweight yote/deer rifle and am not even sure there is a twist that will shoot a 75/80 yote bullet and a 90/100 grain deer bullet. Thought?

 

[dimecovers3]

Gunamonth,
Thanks for taking the time to respond so fully. I have more questions based on your experiences, but first I need to get an idea of what you found to be an average velocity gain in taking the 6mm Rem and AIing it. Based on those numbers, I'll have a few more questions/clarifications. I seriously doubt I'll ever be interested in 115 ultra high BC bullets. Would it be safe to assume 100 grain "deer bullets" are never a problem with AOL? I'm surprised you had so much trouble finding a factory rifle to shoot well. If I bought a factory Rem. 700 in 6mm is it based on a short action? For some reason I thought it might be different from what you get the same rifle in .243 in. I think what I'm going for is a nice Eastern varmint/deer rig that I can use and let my wife or son,when he is old enough use also)I do want it "done right" as I will use it a great deal and want it to shoot sub 3/4 inch with a range of bullets suitable for occasional groundhogs, called yotes, and deer under 300 yards max. I'm thinking 22 to maybe 24 inch 3 or 4 contour and a medium weight rig at the moment. I don't want to go ultra light and handy or medium heavy varmint---just a good compromise that will shoot well, but be compact enough for wife and son to handle well.

 

[vargetman]

I have a 6mm ackley on a Remington medium action that started life as .308. It has a 27 inch Douglas barrel in medium varmint contour in a 1/10 twist with a muzzle brake installed. I shoot Winchester brass with a 75 grain v-max and 49.5 grains of h-4350 with a velocity of 3750 f.p.s./ I have shot 87 grain v-max,x in it also. It is one heck of a ground hog round. I have taken a few hogs and crows at 500 plus yards with this rifle. As for the difference between the 243 and 6mm ackley,s. I think the 6mm ackley will get you more velocity and a little barrel life. This is just my opinion on barrel life. I would highly recommend the 6 mm ackley for varmints or deer sized game. But listen to the other fellow as he has shot both rounds and i bet he knows what he talking about. Hope some of this helps. Thanks John

 

[dimecovers3]

Vargetman,
Sounds like a great rig. I am a little perplexed by the Remington Medium action---I thought they only made a short and long action,and a magnum action) Is the .308 action size bigger than that of say a .223 action from Remington?

 

[chris]

Rem doesn't make a medium action or a magnum action....only short or long....the only difference is the mag boxes, followers, bolt face and feed lips between the calibers...

 

[AndyW]

I went through the exact same decision making process this winter and decided on the 6mm Rem. un-acklied. From my research it was a marginal velocity gain with the .24's going AI. I decided on the 6mm because I would get the same velocity as the 243AI without all of the messing around fireforming brass. One thing I can tell you is that if you want the heavy, high BC bullets to work through a magazine you will want to go .243. My gun is throated so it works with the 70-87 grain bullets all feeding through the magazine. with the 70 SMK I am maybe 1/2 way into the neck getting a good grab. With the 85 SGK and the 87 Vmax I am just barely above the shoulder-neck junction and the loaded rounds JUST clear through the magazine.I'll tell you for sure with a longer bullet it definately would not work as a repeater and it may be grief feeding singles if you had to unchamber a loaded round. My gunsmith was able to make it work with the 70's and the 85's. I get 3750 FPS with the 70 SMK over 45.5 grains of h-414 and with the 85 SGK I get 3350 fps over 39.5 grains of Varget. I get great accuracy with both bullets,average high .3's low .4's with both bullets) If I was to do it all over again I would not change a thing with the bullets I currently shoot. If I wanted to shot the high BC bullets I would probably go with the .243 AI

If it helps in your decision here is the specs on my gun;
Remington 700 SA left hand trued
HS precision Varmint stock
Rob Maclellan varmint barrel 26" 10 twist
chambered in 6MM Rem. w/ a .270 neck
This gun started life as a Remington VSF in .308

 

[AndyW]

Hey dimecovers3,

Adding to my above post have you considered going with the 6br for the bullets you mention? I did a second rifle,same platform as above with a few added goodies) with a 12 twist barrel and this gun is the most fun to shoot! I get unreal accuracy from the 75 Vmax and get 3350 FPS! You will have a little messing around getting the magazine to feed, but other than that it will be good to go. If I was to just own one gun in the 6mm's without a doubt it would be the 6br.

 

[M700]

My 6mm Rem is exactly as Remington built it long ago - a short action, with a sporter weight 22" barrel. It handles 105 grain bullets just fine, have never tried anything longer or heavier.

Favorite deer bullet has turned out to be Nosler's 95 grain Ballistic Tip. Accurate, and does the job on mule deer.