300 Win Mag on an SB2?

[jkpq45]

Saw in the FAQ sticky that 300 Winchester Magnum may have been a cartridge for which the SB2 was chambered (once upon a time).

Any idea why they quit?  Or am I misinterpreting what I saw in the sticky?  Sounds like an interesting idea for a monoblocked SB2 "upper"!

Thanks!
jkpq45

[quickdtoo]

It was never made, the Handi-Mag frames were never made for them, it was cancelled before it even got off the drawing board, H&R listed them in the 2008 2007 catalog, they never got enough distributor pre-orders to justify doing the testing of the new frame, it ended up cancelled before the 2007 SHOT show.

Tim

[jkpq45]

Hmmm.  I'm assuming the SB2 isn't strong enough for such a critter?

[quickdtoo]

Not for long at SAAMI max pressures, might last a while depending on the load, but eventually it would likely fail, I suspect they would have had to improve the underlug also, I think it would have been an entirely different platform so the mag barrels couldn't be used on the SB2 frame. 338 Win mags were also planned.

FWIW, Fanner50 made a 350 Jacob which I think is a 338WM necked up to 358 and Ackley'd IIRC, but he shot reduced loads in it, also had a bolt gun chambered in it.

Tim

[jkpq45]

Hello Quick,

Thanks for the quick response.  What sort of failure would result in an overpressure round being chambered on an SB2 frame?  Break-action breaking open?  Might lend new meaning to the term break action.

Thanks,
jkpq45

[Ten Ring]

The Jacob was a 300Winmag upped to 35, it shot well.
jim

[quickdtoo]

Hello Quick,

Thanks for the quick response.  What sort of failure would result in an overpressure round being chambered on an SB2 frame?  Break-action breaking open?  Might lend new meaning to the term break action.

Thanks,
jkpq45

Action flex is the culprit when approaching max loads even with 30-06 class cartridges which have a smaller case head, that and underlug setback, both are well documented here, flex in the action results in a gap between standing breech and the barrel after the shot before opening the action, underlug setback is evident by the barrel being loose on the frame. Catastrophic failure isn't likely unless  overloaded, then nasty things can happen, one of which is it blows the trigger guard out.

Tim

[quickdtoo]

The Jacob was a 300Winmag upped to 35, it shot well.
jim

Thanks Jim, CRS ya know!!  FWIW, the RL15 load Gary was using is considerably lower than what I shoot in the Whelen Improved.

Tim

I only have 2 rifles left to my name a H&R in 218 Bee and one in 350 Jacob (my own wildcat). I was hoping for the new magnum action, as were many of you, but it didn't happen and I already had a 35 Whelen barrel at Wayne York's being re-chambered and a muzzle brake being installed, so I have made do. The 350 Jacob is a belted magnum made from a 300 WM necked out to .358 and then fire formed to a 40 deg shoulder with no case taper. I guess you could call it a 358/300WM/AI but I named it after my son who was 1 yo at the time hence the "350 Jacob". In Jake's Winchester 70 our loads have cronoed 3250 fps with a 225 gr Nosler guite obviously too much for the Handi to handle, but the solution is the same one that 45-70 owners have done for years. There's 45-70 Trapdoor, 45-70 lever and 45-70 high power loads for Ruger#1 etc. I took my elk last season with a 225 nosler over 56 gr of R15(35 Whelen) and it did just fine, so I started the 350 Jacob at 57.5 gr of R15 and a 200 gr Hornady just to see what I would get and to fire-form some cases.The results were magnificent. No sign of pressure, very little recoil (Wayne's muzzle brake helping here) and accuracy a go-go (showing my age there) 5 shots all touching at 100 yds. In the initial development of the round I discovered many starting loads that gave moderate speed with great accuracy. I have always felt the 300 WM was a great round but seemed to need hot loading to do it's best. When enlarged to .358 the case becomes much more efficient and when fire-formed the cases have very little case stretch or shoulder separation (as touted by PO Ackley). I'm going to keep working along these lines with Nosler 225's and Barnes 225's as well as the Hornady 200's. The late James M. Stanley , gunsmith, engraver and my hunting buddy would say"Speed ain't everything lad, ya got ta hit it first". I'll try to post some pic's and crono reports in the future for those of you that are interested.
Regards to all - Fanner 50 aka Gary

[Ten Ring]

I wouldn't have tried it without all the data you sent me from your loading data. I hated to get rid of ot but Fanner ask me and I sold it to him for what I paid. I hope he is doing well I haven't heard from him in a while.
Jim

[quickdtoo]

I used to get an email from him every once in a while, but he hasn't been online since January. 

Tim