.223 rate of twist question...

sisu1 · 04-16-2005, 09:50 PM

I just purchased a Tikka T3 Varmint .223 with a "1 in 8" twist and have a Nikon Monarch 4X12X40 on order.

From what I understand, the faster rate of twist is intended for primarily heavier bullets. I've read some material on the subject but still don't totally understand "rate of twist" and how it relates to bullet selection. I'm not a handloader (yet) and sure would appreciate any advice concerning factory ammo and bullet selection.

I plan on shooting the rifle at the range with my 13 yr. old son and thinning out the coyotes I should've taken out last deer season.

Gundigest · 04-17-2005, 11:03 AM

Take a look at my 70gr tripple shock x bullet for .223 post. It has a lot of twist rate/bullet weight discussion on it.

But typically the heavier and longer the bullet the faster the twist rate has to be to a certain point.

Roskoe · 04-17-2005, 03:13 PM

One thing that may have gotten lost in all the smoke and boloney spread through the "70 grain Triple Shock for .223" thread is the fact that the fast twists will very often shoot the lighter bullets well - but the slow twists will never work with a long heavy bullet. One of the most accurate bullets in many 1:9 twist .223's is the 50 grain V-Max. The "ideal" twist for a 50 grain bullet may be around 1:15 - but the results speak for themselves. Don' be afraid to try any factory load with a bullet weight of 77 grains or less. And for varmint hunting, I would stick with 50 or 55 grain fast-expanding bullets.

rost495 · 04-17-2005, 06:01 PM

8 twist in 223 should work fine for anything from 40-45 grain up to any 80 grain bullet. I shoot 52s in my 6.5 twists quite a bit so don't be afraid of the light bullets as mentioned.

Along the way try out the 75 amax as a heavy hunting projectile. Its worked very well for me. Probably because I can't drive it fast enough to make it into and explosive round, only one that opens reliably and is accurate for longer ranges. A coyote the other morning never knew what clipped him out the side door of the house at about 200 yards when the 75 got there.

Jeff

Roskoe · 04-17-2005, 08:55 PM

Jeff - I'm curious how much expansion you got out of the 75 A-Max on coyotes. Back at the end of March there was some discussion here on this subject . . . . the 75 A-Max seems to be a pretty good medium big game round at maximum speeds - wondered if they would open up fast enough to deliver the goods to Wile E. Coyote. I guess I answered my own question; but did it just start really opening up about when it exited?

rick_reno · 04-18-2005, 08:22 AM

In that gun, I'd try anything at or under 70 grns. My Sako .223 likes Noslers, I think they're 52 gr.

rost495 · 04-18-2005, 08:43 AM

Roskoe

Shot was just short of my 200 yard mark (he happened to be standing or walking down my rifle range so ranging was easy with all my benches etc...)

MV should have been about 2740 in a 20 inch tube but this was shot in my 26 inch upper so I suspect maybe a bit faster.

Anyway it was .224 entry and looked like it basically went behind shoulder and exited out center neck. Exit wound was not any larger than a dime max. Maybe just a bit smaller. Did not do anything scientific but it appeared basically double the bullet size for exit + a tad.

I've got entry and exit wounds on deer out past 500 yards that act about the same.

I have not shot anything real close with the round though. Actually nothing less than about 160 or so. It may well blow up if close. But since the speeds are under 3K for sure, I suspect its one reason it holds together for me.

Jeff

Roskoe · 04-18-2005, 11:22 AM

In the article by Horace Gore from the "Journal of the Texas Trophy Hunters", they were pushing the 75 A-Max at about 3700 fps out of a .22-6MM. At these high impact velocities, the bullet was penetrating a short distance and then blowing up. On a deer lung shot, this was delivering some very consistent "light out" kills. It sounds like, at lower speeds, it turns into more of a controlled expansion pill. This bullet, which I'm sure was never designed for anything but punching holes in paper, continues to impress me. . . . .

Ridge Runner · 04-18-2005, 01:50 PM

check out the 6th item down on this page, needless to say thats a long ways, especialy with a 223
http://www.sskindustries.com/contender.htm
RR

Roskoe · 04-18-2005, 02:18 PM

Doesn't look like very violent expansion on this hapless prairie dog. There is a guy out here named Bruce who supposedly holds the Guiness record for longest prairie dog shot - something like two miles. I think he shot out a rifle in the process . . . .