September 8, 2012, 09:19 PM | #1 |
Junior Member
Join Date: September 8, 2012
Location: Northeast Indiana
Posts: 10
|
Bullet weight
I have a Savage Axis in .308 Win. Their website says 22" barrel and twist is 10 which i assume to mean 1 in 10. Correct? I have been instructed that faster means lighter bullets, and slower means heavier bullets for great accuracy. Is that true and is 1:10 fast or slow for this rifle? If so, do i want to set up for 150 gr. 180 gr. or 165 gr bullets? Or can I switch around with rezeroes in between and still achieve at least repeatable hunting accuracy out to say 300 yds? (and no I don't think it'll ever be 300 yds, just a reference number)
|
September 8, 2012, 09:38 PM | #2 |
Senior Member
Join Date: November 5, 2008
Location: Spokane, WA
Posts: 1,347
|
in a .30 caliber rifle, 1:10 is a FASTER twist. translates to 1 twist in 10 inches. Therefore 1:12 is SLOWER.
The three bullets you mentioned should all work fine in a 1:10. THe M1 Garand and the M1A have 1:10 twist barrels (with the exception of some of the newer M1A's). The US military typically ran 150 and 173/175 grain bullets for the most part.
__________________
ΜΟΛΩΝ ΛΑΒΕ VIGILIA PRETIUM LIBERTATIS "The price of liberty is vigilance" America is at an awkward stage. It's too late to work within the system, but too early to shoot the bastards. |
September 9, 2012, 01:36 AM | #3 |
Senior Member
Join Date: March 12, 2011
Location: Washington state
Posts: 1,558
|
For that rifle and twist you can choose any of those mentioned and more. Heavier bullets need faster twist. Choose your bullet weight for the animal being hunted not the possibility of accuracy. Then shoot several brands to see which bullet your gun likes. For best results use : 150 & 165 grain for deer, black bear, antelope and the like. 180 to 200 for elk, moose, grizzly bear, buffalo. Bigger animals need more penetration=bigger bullets. Coyote, chucks, prairie dog, and such use 100 to130 grain.
__________________
You can't fix stupid....however ignorance can be cured through education! |
September 9, 2012, 06:29 AM | #4 | ||
Senior Member
Join Date: December 24, 2010
Location: Central Louisiana
Posts: 3,137
|
Quote:
Quote:
|
||
September 9, 2012, 08:12 AM | #5 | |
Senior Member
Join Date: June 16, 2008
Location: Wyoming
Posts: 11,061
|
Quote:
For example, lets say you have a 150 grn round nose, flat base bullet, and compare it to the same caliber, 150 grn spear point, boat tail bullet. The later is going to be longer and would require a faster twist to stabilize it or keep it stable. Also, a faster twist will stabilize a shorter/lighter bullet better then a slower twist will stabilize a longer heavier bullet. Taking your 30 cal bullets, a 1:10 will stabilize a 130 grn shorter bullet better then a 1:12/14 will stabilize a 180-190 bullet. The 223s is a better example. The 1:7 the military uses will stabilize the 50-90 weight bullets, but the 1:12 doesn't preform well in anything over 55 grn. Manufactures use the twist that will stabilize the widest range of bullets the customer will use. That's why they use the 1:10 in 30 cal. If you were going to make a Palma rifle using the 155s then people use the 1:12 or 1:14. But most people don't shoot Palma, they hunt and want 150-180 308s, hence the 1:10. Back to the 223s, most manufactures use 1:9 instead of the 1:7. The reason being, the longer, 80-90 223 bullets require the bullet to be loaded longer, meaning they wont fit in the magazines of the ARs and other 223 Gas guns. Those who use the 80 & 90s use then in competition, 600-1000 yards. They don't care that they don't fit the magazines because they have to single load them in matches anyway. Another reason for the manufactures not using the 1:7 for everything is civilian varmint shooter may want the super light 40-50 varmint bullets that have thinner jackets. They want the bullet to come apart so there is lest fur damage (the don't exit) and the break up when the hit the ground, meaning less chance of ricochets. A super light jacked 40 grn bullet (made for the Hornet) could fly a part by over spinning, in the barrel or air. The military doesn't use those thin jacketed bullets. Some military bullets are lighter then others of the same length, such as tracers vs lead core bullet. A good rule of thumb, if everything else is constant, go to the faster twist.
__________________
Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071 |
|
September 9, 2012, 04:13 PM | #6 |
Senior Member
Join Date: June 15, 2008
Location: Georgia
Posts: 10,809
|
You should be fine with most common bullet weights. It might be less accurate with the real lightweights such as 110' or 125's, but most anything 150-200 will be fine.
|
September 9, 2012, 04:46 PM | #7 |
Senior Member
Join Date: November 5, 2008
Location: Spokane, WA
Posts: 1,347
|
As always, Kraig knows his stuff.
__________________
ΜΟΛΩΝ ΛΑΒΕ VIGILIA PRETIUM LIBERTATIS "The price of liberty is vigilance" America is at an awkward stage. It's too late to work within the system, but too early to shoot the bastards. |
September 10, 2012, 02:05 AM | #8 |
Senior Member
Join Date: September 7, 2010
Location: Virginia
Posts: 333
|
Your Savage is a fine hunting rifle. Find the bullet/load that it groups best and stick with it. My humble suggestion is a 165 grains bullet. It is almost perfect the perfect 308 hunting bullet weight and the 1/10 twist will stabilize it just fine.
Happy hunting
__________________
Superman, you are a mean drunk |
September 10, 2012, 11:07 AM | #9 |
Staff in Memoriam
Join Date: November 13, 1998
Location: Terlingua, TX; Thomasville, GA
Posts: 24,798
|
I've found that in a thirty-cal, a 1:10 twist is fine for 110-180 range bullets. Sub-MOA is fairly easy.
So, 110 for coyotes, 150 for deer, and 165 or 180 for elk. |
|
|