Pronghorn cartridge in 6mm

[ImBillT]

So how long a bullet can you get in 6mm? All I'm aware of is 105gr and they are not very common around here. If I though I really needed more than a 87 to 100gr bullet in 6mm, I'd simply step up to 25 cal! BTW, about my 6.5x06. I to have used 270 Win and 280 Rem brass to reload. have never necked up a case for anything and in 6.5x06 using a 25-06 case, I also shoot a 25-06. Be somethig to use those case's to make 6.5x06's then have to neck something else down for 25-06!

Plenty of 115gr bullets out there. Solid coppers are long too. 1-10” twist won’t even fully stabilize the 90gr Accubond. It’ll shoot them fine, you give up BC. A lot of factory .243Wins now use a 1-9.25” twist. Mine is a 1-10”. A 1-8” would be much more useful.

 

[ImBillT]

Ain't no dust on the plain jane .243 either...brass is easy to come by, good velocity, available in all kinds of rifles and if semi-custom you can twist/throat to your liking.

If not for sentimental reasons, I would have re-barreled my ruger 6mm to .243 Winchester.

There reaches a point where messing with brass, AI this and that, wildcats, etc. that it just isn't worth it.

I have no problems with a .243Win. I’d hunt more with my wife’s if it had a 1-8” twist. They’ll fit in short and medium length actions a lot better than the 6Rem, but then again, the 6CM fits even better.

 

[cahunter805]

A) If you want a .020” oversized bullet channel in your seater, and a loose stem to boot, be my guest. Forster uses a .0005” oversized bullet channel. Wilson uses a thousandth or two, I don’t remember, but the seater stem itself has less than .0005” between itself and the bore and centers the bullet on its interface with a perfectly aligned stem. By screwing a 6.5mm seater stem into a die meant for a 7mm stem, the only thing aligning the stem is the is the threads, all you have to do to see the problem with that is wiggle your seater stem.

B) yes you can use a false shoulder, but doing so with proper headspace requires a lot more care and measurement than the average reloader wants to go through. I had to do it with my wildcat initially as I was originally using a die situation similar to what you’re describing, and I can tell you that it is an unnecessary pain in this situation.

C) you’re right. The 17.5 degree shoulder of the 6.5-06 means the neck shoulder junction moves about .044” forward of a 30-06, compared to moving forward about .015” necking a .280AI down, however, I hadn’t realized off the top of my head just how far forward of a 30-06 a 280Rem shoulder is. Still minimal.

D) I haven’t checked PTG, but they usually have quite a few variations of anything remotely standard. They almost certainly have a 6.5-06 reamer print that is a perfect fit for a no-turn neck after sizing down Lapua 30-06 brass with a couple different throat lengths, guaranteed to include a throat designed for the 140VLD. Talk to Dave Kiff and he’d set you up with which print they already have that works best depending on which brass and bullet you want to use. While you’d pay special order price, you wouldn’t have to pay custom price. It’s possible that you’d want something slightly different than what they had, and then you could go full custom. On the other hand, it’s unlikely that too many folks have done much necking down a .280AI, you’d almost certainly have to pay for a custom print.

A- I use Competition seater dies which I’ve switched stems before and had less than .002 runout with. The stem is supported.
B- I agree
C-
D- Don’t use PTG. JGS and Manson are who I prefer. JGS will custom grind whatever you spec out or send them dummy rounds.

 

[cahunter805]

My 8 twist 243 loves 105VLD and is deadly. I personally wouldn’t hesitate to shoot an elk with it.

 

[Nick87]

Another vote for 6mm remington!

 

[ImBillT]

My 8 twist 243 loves 105VLD and is deadly. I personally wouldn’t hesitate to shoot an elk with it.

I’m sure it’s great. I’d up it 115’s if I had one that would work with them. I don’t, and rather than rebarrel a Sako, I’m just going to build a 6mm Rem on a Mauser 98.

 

[cahunter805]

115s normally require a 7.5 twist.
How about a 6SAUM spinning 110SMK? My brother just put one together. Will see how it does! I’m sure a hammer.

 

[ImBillT]

115s normally require a 7.5 twist.
How about a 6SAUM spinning 110SMK? My brother just put one together. Will see how it does! I’m sure a hammer.

Depends on where you’re elk hunting.

I’d say 3400fps is in the cards for him with a 110 in 30” barrel, coated bullets and running hot, but a 6Rem could come dang close. Deduct almost 40fps per inch under 30”.