35 caliber Cast conversion done!

[SCHUETZENBOOMER]

I have a clean sweep on the conversion of my .35 calibers to cast! L to R are the .35Rem, .350GP, .35Whelen and .35 Whelen Ackley Improved. All loaded with Accurate Molds products. I have 40 rounds of the Whelen loaded up for fireforming with those 280gr moose busters. Anxious to get some shooting weather out of the single digits soon.

[DeanWinchester]

What is a .350 GP?
Never heard that one. Looks awesome. Good work!

[SCHUETZENBOOMER]

My own wildcat. It can run thru a short action.

[DeanWinchester]

Kinda like an improved 358 Winchester ????

[SCHUETZENBOOMER]

The “GP” series of cartridges are my own wildcat creation, all based on the 8x57 cartridge. All made to run thru either a short or standard length action depending on seating depth. I have never offered anything commercially, and have mostly just played with load data. The lineup has (10) calibers starting with 6mm and ending with .375. I have extensive chronograph data on several variations and can send an excel spreadsheet if interested. I created these back in the late 90’s and at that time the lineup filled some pretty big gaps in the commercial offerings. My .338GP and .375GP’s are the best examples. Send me an email address that I can send that spreadsheet to and you will find some good examples of what the Ackley “shoulder” can do to load efficiency.

[swheeler]

Nice line up you got there! I would imagine you started with an 8x57 AI and started necking fireformed brass up and down to various calibers. How many of the wilcats did you actually have rifles chamber in?

[SCHUETZENBOOMER]

Its actually not a "pure" 8mmAI, but works out darn close. It all started with the .257 Robert's AI with the shoulder moved forward another 2mm.

I have rifles and chrono data in the 6mmGP, 250GP, 6.5mmGP, 8mmGP, 330GP(which is the .338 listed above), 350GP and the .375GP.

[swheeler]

Sounds like you have one for anything that needs killin' What weights and velocities for the 375 version, should be a real thumper on par with 9.3x62 or 375-06 would guess.

[SCHUETZENBOOMER]

I was not out to create anything but a general purpose round (GP) with the advantages of the Ackley shoulder. Something about that shoulder that seems to eke the most out of powder and accuracy. If I knew how to attach a my spreadsheet, I would be happy to. My boys have about 15 whitetails to the .250GP credit and the results are instant drop. The 6.5mm is one of the most accurate rounds I have ever shot. Seems like it does not care what you feed it, it try's to find zero. The .330GP seems to be just as inherently accurate. I do all my own chambering and barrel work and many of these rifles were quickly thrown together to give me a platform to start collecting chronograph data. All cartridges have the same shoulder height and hence the headspacing is identical. This makes switchbarrels and loading dies a non issue between rifles.

[swheeler]

I like the GP name given and what it stands for, I'm a general purpose type of guy. I also am fond of the Ackley shoulder on cartridges and the advantages, brass that doesn't stretch and throat erosion is measurably reduced plus the benefit of getting every last bit of velocity out of a powder with acceptable pressures. I currently have 7x57 AI, 06 AI and load for 450 Watts AI, brother has 257 Rob AI. Everytime I see an internet thread on the 30-06 AI, I don't bother to respond to the "you'll only gain 50fps" " I read it on the internet" but I've owned atleast a couple dozen 30-06 rifles, loaded for everyone of them and only one has ever given 3100+fps with 150's and 2950+ with 180's, and yes it is AI.

[swheeler]

Just ballpark numbers on the 375 version would be fine, just curious.

[SCHUETZENBOOMER]

Have not really pushed this one at all.

.375GP M98 26" BBL / 1-12"

POWDER / WT. BULLET DESC. PRIMER CASE VELOCITY LENGTH
IMR4064 / 48gr HORN 225gr SPTZ CCI200 REM 2180 FIREFORM LOAD
IMR3031 / 44gr HORN 225gr SPTZ CCI200 REM 2157 3.000"oal
IMR3031 / 45gr HORN 225gr SPTZ CCI200 REM 2279 "
IMR3031 / 46gr HORN 225gr SPTZ CCI200 REM 2348 "
IMR3031 / 46.5gr HORN 225gr SPTZ CCI200 REM 2360 "
IMR3031 / 47gr HORN 225gr SPTZ CCI200 REM 2381 "
IMR3031 / 47.5gr HORN 225gr SPTZ CCI200 REM 2402 "
IMR4064 / 48gr HORN 225gr SPTZ WW/LR REM 2233 3.000"oal
IMR4064 / 49gr HORN 225gr SPTZ WW/LR REM 2289 "
IMR4064 / 50gr HORN 225gr SPTZ WW/LR REM 2366 "
IMR4064 / 51gr HORN 225gr SPTZ CCI200 REM 2314 "ACCURATE!

[SCHUETZENBOOMER]

All data listed is a minimum of 2 (10)shot strings.

[swheeler]

Thanks Schuetenboomer. Looks like your just in 35 Whelen territory with those loads, and that's not a bad place.