How do you decide on an improved cartridge?

[Litehiker]

So JB, are you talking about an "Ackley" improved shape? That shape seems, for some reason, to give decent barrel life and is velocity tolerant.

Eric B.

 

[jb1023]

So JB, are you talking about an "Ackley" improved shape? That shape seems, for some reason, to give decent barrel life and is velocity tolerant.

Eric B.

Well, as I understand it the common characteristics of an original PO Ackley cartridge was 35-40* shoulder, less taper and the parent cartridge could be fired from a AI chambered rifle. That being the case, then yes, I am talking about an AI shape.

That being said, Swamplords 338 PRO looks pretty enticing even though it cannot fire parent cased ammo.

 

[J E Custom]

So I think I want to go with a chambering that will allow me to shoot parent case ammo and I want the shoulder between 35-40*. I have looked up where to buy a reamer and came up with 4 makers. PTG seems to be the biggest or at least the one I see mentioned around here the most. There is also Manson, Clymer and JGS. Is PTG the place to go or perhaps I should ask if there is one I should avoid? I recall reading about one whose service went to hell a few years back and several posters had to send their reamers back as they were not correct and they were getting grief and such but I don't recall which it was. I'm guessing all of their prices are fairly close. I will be doing my own research but thought I would ask here as well.

In my opinion, the best reamer makers are Manson and JGS, Clymers are good But I don't buy any Pt&g reamers any more.

Go with a standard Ackley Improved cartridge because you can fire form the parent cases/cartridges with great accuracy and ease. Most are 40o shoulders and with center feed mage boxes the 40 o shoulder is the optimum.

J E CUSTOM

 

[L.Sherm]

In my opinion, the best reamer makers are Manson and JGS,

This^^^

 

[highdrum]

The only necessary reason to improve the norma case is to stop brass flow into the neck, as the oem norma brass is soft and you'll be trimming necks and fighting donuts. The additions of peterson lapua adg brass that's much stronger may negate that problem. My rifle is almost finished, it's standard 300 norma with 225 freebore. I have peterson & Bertram brass. If I have problems with brass, constant trimming, donuts I may set the barrel back a few threads and improve to 30-35° shoulder and reduce taper some.

 

[Swamplord]

the addional 10 gr of capacity improvement benefits in pushing this heavy 400 gr bullet in my 400 Skuldryl

 

[jb1023]

View attachment 111251 the addional 10 gr of capacity improvement benefits in pushing this heavy 400 gr bullet in my 400 Skuldryl

WOW, not something I will ever own but man that is mean looking. What kind of velocities are you getting with those 400's?

 

[jb1023]

So I'm still torn between the 300 and 338 but I have settled on a 40* shoulder and thinking 1-2% body taper. I'm leaning towards the 300 just because it looks like it will get me to 2k yds and still be supersonic(ish) with a 215-230 projectile (225 ELD-M @ 3100 behind RE33), which was my original goal. Ryan is getting 3300 from a 215, don't know what his load is but wow. 2K is my goal, will I ever obtain it, at this point who knows, but I'm planning ahead. And the 300 will do it with less felt recoil, I'm told, and less cost per trigger pull. Granted the savings will likely be offset by shorter barrel life but with as often as I shoot that should still get me to 3-5 yrs when factoring in my other rifles.