Building a 7 stw
Does anyone know about the parent cartridge for the 7 stw? I think it is possibly one of a kind. I have a 300 remington ultra mag. Would the ultra mag action require bolt work to build into a 7 stw? Any information will be appreciated. Any one near Indiana interested in building this for me?
0
-
I beleive that the 7mmSTW is the 8mmRemMag cartridge necked down to 7mm with little to no other changes. The 8mmRemMag is a necked down and improved version of the 375H&H case. I think that the UltraMags are based on one of the larger diameter case headed cartridges, either the 416 Rigby or the 404 Jeffery, and so is larger then you would want to use with the 7mmSTW. If you have an UltraMag action it would make sence to build a 7mmUltraMag. The STW that I keep thinking about putting together would be built on a Ruger no 1 action with a 28" barrel. These larger hulls need longer barrels to get all the velosity that is available. 28" barrels on a bolt action makes for a very long rifle. Good luck ....... 0 -
Troy,
The 7mm STW is indeed the 8mm Rem. Mag. necked down for the .284 bullets. It's regaining popularity with the long range hunters and even some of the long range target shooters based on the availablilty of some new bullets.
Your rifle would be better suited to using the 7mm Rem. Ultra Mag. (RUM) as opposed to fitting it for the 7mm STW because of the case size of the RUM. The bolt won't require any change but the feed rails and ramp will take a bit of fussing to get the somewhat smaller case to feed correctly. The RUM magazine will have to be changed out for a regular long magnum magazine. Going from larger to smaller is a bit problematic but it can be done. There will be some that contend that you can just throw the STW cases in and go shoot but reliability will be an issue. If you want the rifle to feed reliably 100% of the time some adjustments will have to be made.
Look into the 7mm RUM and forgo the alterations and cost. In fact, you can probably find a new take-off barrel for not much money and have a gunsmith adjust the headspace and you're ready to go hunting with a minimum investment. Reloading for the Rum will maximize its efficiency and effectiveness.
Check into AA 8700 powder for reloading information:
http://www.accuratepowder.com/
Here are two surplus powders to check:
Virgin New WC-872, Virgin Magnum rifle ball powder, use H870 starting data to work up all loading data. 8#-$36.00,
WC860, US Government 50 BMG Powder, Magnum Rifle powder, Have not had this number for several years, found a small supply, 8#-$39.00.
http://www.patsreloading.com/patsrel/prices.htm
And more surplus:
WC872(n) Original application is U.S. 20mm Vulcan ammo. A ball powder which
can be loaded using Hodgdon H870 or AA8700 data.
This is new ball powder.
$40/8# jug.
WC860 Original application is U.S. .50 Cal. BMG ammo, used for the Ball
M33 and API M8 projectile. A ball powder which can be loaded using
Hodgdon H870 or AA8700 data.
This is pulldown ball powder.
$40/8# jug.
http://www.gibrass.com/gunpowder.html
Here are the drawings for comparison:
0
Please sign in to leave a comment.
Comments
2 comments