So we're happy happy happy with my newest "338WSM Matson #2" iteration.
Wrapped shooting at 10:21PM to great applause.
Been dinking with the WSM case for some time now to great success ...short, long etc, most are set at -.006 from 'GO'........ our latest craze is to run in to crushfit on RUM brass....270, .300 325 and latest is 338 ((Holy Smacke'Roni she makes the 338 EDGE run and hide)) but tonite was running a "standard" 338WSM crushfit at -.006 from the Go-Gage starting with a 28" barrel and cutting back, testing, with the stated goal being to achieve "2400+fps from a 24" bbl with a suppressor shooting 300gr OTM's" and run up towards 2500fps if it's humanly possible. We're testing a naked full length Shilen blank at about 28 inches.
338WSM with 300's is veritably unknown territory.
24" bbl w/300gr bullets is unknown territory
Even 28" is kinda' unknown to us as most of my big 338's are 29"-32" plus the brake using a huge case.
I make EDGE's, send 'em out with safe loads running 2750-2850. Can stretch this if can get good brass.
I make 338 Lapuas @ 2800-2850 but weather-specific....
I make my brainchild the 338 McCallum, a blown out 338 Lapua and some guys push them to 3000 but case life is short....2900 is better, 2750 is all-weather safe.
I also do 30-378, 338-378 and 378 Weatherby's with the 338-378 being "analogous" to our 338 testing
Point is, I finally about 6mo ago took delivery of a 338WSM on my FatButt design. I spec'd it for my 1000 case lot of Winchester cases, guessed at the blowout length and ran for .227 freebore and 1*30 leade angle and tonite we took ONE Winchester 300WSM case from 54gr starting load (taken from Berger reloading data as near max load) on up...
and up....
and uuppp.......
We did no sizing.
We poked the primers out with a LE Wilson pointy-primer-poker-outer setting the case on a upside-down shellholder and whacking with a hammer and re-primed and poked a bullet back in with our fingers and ran 'er UUPPPP-EDDY-UUPPP!!! shooting 2 rds per load to an un-specified point where the primers finally started to loosen.
The primers FINALLY started to loosen at 15 firings bumping up to well over the listed loads
At over 2700fps
HOleee KuhRAPPP!!
16 firings on one single Winchester WSM case and 2700fps w/300's.
We now expect to easily be making 2450-2500 with the can on and a short huntable package
So yeahhh.... I be feel GOOD about this latest WSM reamer
edited to add 2700fps IS NOT A SAFE LONG-TERM LOAD FOR 338WSM USING 300'S IN A 28 INCH BARREL! At least not with the quarter-inch freebore.
But 2600+ looks to be eminently doable. I feel that with care 2650 is solidly achievable. WITH the long 28" barrel. And that running within 100-150fps of the huge magnums is outrageously satisfactory. Fully 50% less powder, with concurrently less ablation/heat....... I count the 338WSM a success.
A long action is required.... and there's still lots of room for throating 'er out..... and yes, with careful tweaking and a maybe 1/2" freebore (bullets still seated firmly into the lands) I'm excited about the possibilities.
Wrapped shooting at 10:21PM to great applause.
Been dinking with the WSM case for some time now to great success ...short, long etc, most are set at -.006 from 'GO'........ our latest craze is to run in to crushfit on RUM brass....270, .300 325 and latest is 338 ((Holy Smacke'Roni she makes the 338 EDGE run and hide)) but tonite was running a "standard" 338WSM crushfit at -.006 from the Go-Gage starting with a 28" barrel and cutting back, testing, with the stated goal being to achieve "2400+fps from a 24" bbl with a suppressor shooting 300gr OTM's" and run up towards 2500fps if it's humanly possible. We're testing a naked full length Shilen blank at about 28 inches.
338WSM with 300's is veritably unknown territory.
24" bbl w/300gr bullets is unknown territory
Even 28" is kinda' unknown to us as most of my big 338's are 29"-32" plus the brake using a huge case.
I make EDGE's, send 'em out with safe loads running 2750-2850. Can stretch this if can get good brass.
I make 338 Lapuas @ 2800-2850 but weather-specific....
I make my brainchild the 338 McCallum, a blown out 338 Lapua and some guys push them to 3000 but case life is short....2900 is better, 2750 is all-weather safe.
I also do 30-378, 338-378 and 378 Weatherby's with the 338-378 being "analogous" to our 338 testing
Point is, I finally about 6mo ago took delivery of a 338WSM on my FatButt design. I spec'd it for my 1000 case lot of Winchester cases, guessed at the blowout length and ran for .227 freebore and 1*30 leade angle and tonite we took ONE Winchester 300WSM case from 54gr starting load (taken from Berger reloading data as near max load) on up...
and up....
and uuppp.......
We did no sizing.
We poked the primers out with a LE Wilson pointy-primer-poker-outer setting the case on a upside-down shellholder and whacking with a hammer and re-primed and poked a bullet back in with our fingers and ran 'er UUPPPP-EDDY-UUPPP!!! shooting 2 rds per load to an un-specified point where the primers finally started to loosen.
The primers FINALLY started to loosen at 15 firings bumping up to well over the listed loads
At over 2700fps
HOleee KuhRAPPP!!
16 firings on one single Winchester WSM case and 2700fps w/300's.
We now expect to easily be making 2450-2500 with the can on and a short huntable package
So yeahhh.... I be feel GOOD about this latest WSM reamer
edited to add 2700fps IS NOT A SAFE LONG-TERM LOAD FOR 338WSM USING 300'S IN A 28 INCH BARREL! At least not with the quarter-inch freebore.
But 2600+ looks to be eminently doable. I feel that with care 2650 is solidly achievable. WITH the long 28" barrel. And that running within 100-150fps of the huge magnums is outrageously satisfactory. Fully 50% less powder, with concurrently less ablation/heat....... I count the 338WSM a success.
A long action is required.... and there's still lots of room for throating 'er out..... and yes, with careful tweaking and a maybe 1/2" freebore (bullets still seated firmly into the lands) I'm excited about the possibilities.
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