.300 win mag custom build barrel help
- Thread starter madashell
- Start date
Why gain twist?
I'm not sure what reamers are our there but if it were me, I'd get it throated for the Berger 230s. There's a good article out there by Applied Ballistics comparing the .300wm to the .338 Lapua and the WinMag doesn't give up much to the Lapua when pushing the 230s...
I'm not sure what reamers are our there but if it were me, I'd get it throated for the Berger 230s. There's a good article out there by Applied Ballistics comparing the .300wm to the .338 Lapua and the WinMag doesn't give up much to the Lapua when pushing the 230s...
why a gain twist?
what do you want to do with the rifle?
if it can help you:
I built my 300wm on a tac300 with a benchmark lightpalma 28'' 1-10 5R col with 200 accubound is 3,700 and seated at 0.050 from riflings. this gives lots of room for powder and reloading data is useless. I get at 1/2 moa consistent at 3035 fps with GM215M primers and H1000
I used a PTC tac reamer and a throat reamer to push the bullet where I wanted it
it mag feeds well with a accumag 3,775. I can put only one round in a BDL kit and its there only in case first dont fire. I never needed the second shot.
how you build it goes with what you want to get from it.
.300wm to the .338 Lapua and the WinMag doesn't give up much to the Lapua when pushing the 230s
my 338 LM with 300 berger COL 3,9'' in benchmark 3C 1-9,5 32'' goes little over than 3000 so you should compare aples to aples.
what do you want to do with the rifle?
if it can help you:
I built my 300wm on a tac300 with a benchmark lightpalma 28'' 1-10 5R col with 200 accubound is 3,700 and seated at 0.050 from riflings. this gives lots of room for powder and reloading data is useless. I get at 1/2 moa consistent at 3035 fps with GM215M primers and H1000
I used a PTC tac reamer and a throat reamer to push the bullet where I wanted it
it mag feeds well with a accumag 3,775. I can put only one round in a BDL kit and its there only in case first dont fire. I never needed the second shot.
how you build it goes with what you want to get from it.
.300wm to the .338 Lapua and the WinMag doesn't give up much to the Lapua when pushing the 230s
my 338 LM with 300 berger COL 3,9'' in benchmark 3C 1-9,5 32'' goes little over than 3000 so you should compare aples to aples.
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Well I'm in the same position, and after talking and taking advice from my colleagues, I've decided on a Bartlein blank, finished length of 28" with a break, 11.25 twist, 5R, I went with a REM varmint/sendero contour. I'm looking at shooting 185's and up at 3000+ mv. You really want the longest barrel to take advantage of all that powder.
Ya it took ALOT of convincing to get me to go to the longer length, I like 20" barrels, I suppose you could go 24" or 26" like the M24?. I will have a pretty good "recipe" for 185 Bergers.I"m new to long range and 300mag, so I took the advice of some folks who had "been there done that".
Here's the article I was talking about. It compares 24" 300 winmag to 24" 338 Lapua magnum. Pretty apples to apples, I'd say
For twist rate, 1:9 works better for anything over 200 grs. Litz has a stability calculator. 1:10 will work at altitudes above sea level and temperatures above 0 celcius. 1:9 works all over. I don't think gain twist is a bad idea. Snipers hide reviewed one and it shot well. Fill your boots!
For what it's worth, you could always look into the 7 mm Rem Mag with the new 195 gr EOL's?
(7 mm RM) 195 gr EOL G7 BC: .387
(300 WM) 230 gr Hybrid G7 BC: .368
(338 LM) 300 gr OTM G7 BC: .421
Both the 7 RM and the 300 WM will give up performance to the 338 LM, but there is not a hell of a lot between them sub 1700 m, IMHO.
As a side note, I'd be looking at a longer (26"+) barrel for a purpose built long range target rig, and you may want to check out this new, little Canadian barrel manufacture called "International Barrels".
They have 300 WM barrels and 30 cal barrel blanks for sale right now for good prices
(7 mm RM) 195 gr EOL G7 BC: .387
(300 WM) 230 gr Hybrid G7 BC: .368
(338 LM) 300 gr OTM G7 BC: .421
Both the 7 RM and the 300 WM will give up performance to the 338 LM, but there is not a hell of a lot between them sub 1700 m, IMHO.
As a side note, I'd be looking at a longer (26"+) barrel for a purpose built long range target rig, and you may want to check out this new, little Canadian barrel manufacture called "International Barrels".
They have 300 WM barrels and 30 cal barrel blanks for sale right now for good prices
Thanks for the information Kudu but I'm set on the .300wm.
Will check out your barrel company suggestion. Searching now ..
Will check out your barrel company suggestion. Searching now ..
For what it's worth, you could always look into the 7 mm Rem Mag with the new 195 gr EOL's?
(7 mm RM) 195 gr EOL G7 BC: .387
(300 WM) 230 gr Hybrid G7 BC: .368
(338 LM) 300 gr OTM G7 BC: .421
Both the 7 RM and the 300 WM will give up performance to the 338 LM, but there is not a hell of a lot between them sub 1700 m, IMHO.
As a side note, I'd be looking at a longer (26"+) barrel for a purpose built long range target rig, and you may want to check out this new, little Canadian barrel manufacture called "International Barrels".
They have 300 WM barrels and 30 cal barrel blanks for sale right now for good prices
