With so much intrest in the 7 STW I decided to go through
my reloading notes and see if I could help those new to
I will share what my experience was with the STW and hope
others like varmint hunter will share thier's ,for an overall view
of the big 7 .
On a previous post I spoke about the velocity bug and how
bad I had it,so I set out to have one of the flatest shooting
rifles around. Remember this was when the STW was strictly
a wildcat based on the 8mm Rem Mag case.
Then as is now the longer the barrel the higher the velocity,
so I started with a 32" .284 1in91/4 twist with a finished
length of 31" This was as long as you could get at the time.
To keep the overall length of the rifle to a minimum I chose to
build it on a Browning B 78 action. Realy a nice hunting rifle
for the area of west texas that I hunted.Average shots were
300 to 400yrds with some being 800 to 900yrds so a flat
shooting rifle would come in handy.
First I started with the 120 gr bullets and exceeded 3800 ft/sec
but accurace fell off at 3680 no mater what load I used and the
best group with the 120's was a dissappointing 1.228 @ 100yrds
So after 31 different loads I gave up on the 120's.
Next I tried the 140;s These were very flat shooting @ 3625ft/sec
(my hot'est accurate load)using 7828 .RELOADER 22 gave me 3538
ft/sec but poor standard deviations (23)and H1000 was 3532ft/sec
with a SD of 15. H 5010 gave the best overall performance at 3537
ft/sec and a SD of 9. group size was .393 @ 100yrds.
I like to load at 100% case density an H 5010 worked well and was
not so temperature sensitive.
The main problem with the 140 gr bullets was 300 to 400 yrd shots
required bullets like the Nosler partition or Swift A frame and 500yrd
to 1000 needed thin jacketed bullets like the Blistic tip to perform
on deer size game.
Rather than hunt with two different bullets I decided to try 150 and
160gr bullets and give up some velocity. At 3374 ft/sec I did'nt loose
much trajectory and bullet performance was very good.
Also all of these loads liked the Rem 91/2 Mag primer better than the Fed
215 .The feds gave higher velocities but the 9 1/2s gave much better
standard deviations and groups.
Powders that seemed to work were.=H1000,IMR 7828,reloader 22 and
H 5010 with 5010 being the best in my rifle.
Also all of the best loads used 8mmRM necked down and outside neck
turned to max thickness for bullet grip.
I did'nt include powder charges because these loads could be hot in
other rifles so work up slowly.
This information came from over 200 different loads and thousands
Good luck with this information and I hope others will post there
findings so I to can learn more about this round.
J E CUSTOM