Ever since Ross Seyfried wrote that article on the Mach IV I have lusted for one.
I decided if I could size some 7 rem mag brass down to 6mm/7 Rem mag or use 264 win mag brass with existing dies I would give it a try.
The forming was very easy. Used the 264 win mag FL die then followed it with a 270 bushing die in a 7mm Rem mag Redding S bushing die. I have a 7 rem mag redding body die too. Seating can be accomplished by properly adjusting a 257 Weatherby Redding competition seater die. Runout is very low.
I had a PT& G 7 Rem mag reamer. For a small fee they will regrind to the new dimension.
I have a LA Rem 700 with a magnum bolt face that will be used with Remington 243 takeoff barrels. I have a lathe and all I have to do is rechamber. The takeoffs fit the receiver with no threading or cutting of the bolt face recess. All I have to do is setup the Lambeth-Kiff micro adjustable reamer stop from PT & G so headspacing is a breeze.
Micro-Adjustable Reamer Stop From PT&G « Daily Bulletin
I experimented with a 20" Rem 243 takeoff in 6mm-284 to see if I could stabilize the 105 Berger hybrid with the 1 in 9 1/8 twist. Berger's twist rate calculator showed a SG of approx. 1.25 which is considered marginal stability. BUT I was able to get some good results at 100 and 546 yds with relative slow velocities of 3150 fps.
http://www.bergerbullets.com/litz/TwistRuleAlt.php
The plan is to try and duplicate a heavy (20 lbs) 28" 6mm-284's performance in a lightweight sporter. Velocity goal is 3500 fps. I intend to use Rem takeoffs for all experiments. I have a 24" which will be used first. Have a 26 varmint 243 takeoff for second barrel. Will be using US 869 or RL-33 as the powders.
IF the Berger hybrid doesn't work then the 105 Hornady A-max is second choice.
If I find this exercise to be futile I can always have the reamer reground to more mundane dimensions like a 6mm-06.
Thought I'd share this with my fellow LRH rifle enthusiasts. Stay tuned for results in a few weeks. (waiting on return of reamer)
I decided if I could size some 7 rem mag brass down to 6mm/7 Rem mag or use 264 win mag brass with existing dies I would give it a try.
The forming was very easy. Used the 264 win mag FL die then followed it with a 270 bushing die in a 7mm Rem mag Redding S bushing die. I have a 7 rem mag redding body die too. Seating can be accomplished by properly adjusting a 257 Weatherby Redding competition seater die. Runout is very low.
I had a PT& G 7 Rem mag reamer. For a small fee they will regrind to the new dimension.
I have a LA Rem 700 with a magnum bolt face that will be used with Remington 243 takeoff barrels. I have a lathe and all I have to do is rechamber. The takeoffs fit the receiver with no threading or cutting of the bolt face recess. All I have to do is setup the Lambeth-Kiff micro adjustable reamer stop from PT & G so headspacing is a breeze.
Micro-Adjustable Reamer Stop From PT&G « Daily Bulletin
I experimented with a 20" Rem 243 takeoff in 6mm-284 to see if I could stabilize the 105 Berger hybrid with the 1 in 9 1/8 twist. Berger's twist rate calculator showed a SG of approx. 1.25 which is considered marginal stability. BUT I was able to get some good results at 100 and 546 yds with relative slow velocities of 3150 fps.
http://www.bergerbullets.com/litz/TwistRuleAlt.php
The plan is to try and duplicate a heavy (20 lbs) 28" 6mm-284's performance in a lightweight sporter. Velocity goal is 3500 fps. I intend to use Rem takeoffs for all experiments. I have a 24" which will be used first. Have a 26 varmint 243 takeoff for second barrel. Will be using US 869 or RL-33 as the powders.
IF the Berger hybrid doesn't work then the 105 Hornady A-max is second choice.
If I find this exercise to be futile I can always have the reamer reground to more mundane dimensions like a 6mm-06.
Thought I'd share this with my fellow LRH rifle enthusiasts. Stay tuned for results in a few weeks. (waiting on return of reamer)
