20" 1/7 twist barrel with .223 55gr

[CarRacer]

I was picking the brain of a very experienced reloader today to gather information on loading .223 myself. I told him my plans for shooting were 3 Gun and that I planned to shoot Hornady 55 grain FMJ Boat tails. He cautioned me about shooting that light of a bullet out of a 20" 1/7 twist BCM barrel.

Should I rework my plans and start researching other loads in my manuals or can the Hornady handle being spun like that and still deliver if I do my part?

Thanks for any information.

[RiggerJJ]

He is probably right, try em thou to be sure cause they are pretty good bullets for 3gunning, its right on the ragged edge from what I understand. Personally I wouldn't go tighter than 1/8 for 55fmjs. Some 55jhps may work better thou, depends on their profile.

Good luck, I understand the reasons...

jj

[pjb45]

I think classic wisdom is the 1/7 twists stabilize the heavier bullets while the 1/9 are great for the lighter bullets.

That said, one of the smartest people I know, former VV technical rep for USA, said the 1/9 can stabilize a 69-75 gr bullet.

I suspect the concern being raised is producing too much rotation for the 55 gr bullet out of a 1/7. Hornady is a premier bullet, try it and see what you think. I have shot with guys using 55 gr with a 1/7 twist barrels and there were no problems.

Personally, I standardized my 1/8 JP to 69gr SMK for all my reloading. I have used XM193 55 gr out to 400+yards with no problems.

Out of my JP, Hornady 55 and 75 gr bullets have almost the same dope. The XM 193 are almost the same as my 69gr SMK.

Maybe I am more tolerant than most, since I am trying not to achieve bench rest type accuracy. I am more than satisfied with an MOA of 1/3..

[redial]

They'll work fine.

My standard 100 yard practice loads for Highpower, from similar barrels are 52 gr match bullets and 55 "whatever's on sale". The 52's shoot snarly bugholes from prone and the lesser ones still go to call.

Mark

[mpeltier]

His cautions are well placed. However, though some have reported satisfactory results shooting 55gr in a 1/7 twist I have not had a 1/7 that shot the 55gr nearly as good as 75grs. My current 20" 1/7 shoots 75's into well under 1" but will not shoot any 55 better than 1-1/2" to 2". By contrast my 1/9 bbl shoots the same 55's under 1". Some would argue that 1-1/2 to 2 inch groups is satisfactory, but I prefer as much accuracy as can reasonably be achieved.

[californiasushi]

I'm shooting a 20" WOA 1:7 barrel with thousands of rounds through it and have been trying to use up the rest of my Winchester 748 developing a Hornady 55gr FMJ load for it. I settled on a 27gr charge. For some reason, I'm getting a couple fliers per 10 shots. I still need to test the load further but I'm somewhat pleased with the results for now. Even with the two fliers this 10 shot group from 100y is still about 1.25" but the main group is smaller.

Edited November 6, 2013 by californiasushi

[MarkCO]

Sure, they will work fine...for a while. The problem becomes one of barrel wear. The lighter bullets, at faster speeds and typically hotter powders significantly increase barrel temps with faster twists. This leads to gas port erosion and to a lesser degree, throat and muzzle crown issues. So for 69s out of a 1/8 you might get 12K rounds, with a 55s in a 1/7, you might drop to 9K rounds before the barrel loses half of its original accuracy potential. Sure, the actual life of a barrel is measured in seconds (really, do the math) and the faster twist combined with the higher velocities is a significant wear factor.

I have been able to shoot tiny groups with 50s out of 1:7 barrels as long as I only do it once in a while and keep the number of rounds at a time very low. We just don't do that much in 3Gun. For High Power, they don't shoot fast enough for it to matter as much, but it will still reduce the life of the barrel.

When the barrel has gone south and you shoot some light or thin jacket bullets, you start to get puffs of exploding bullets. When they shed the jacket in the barrel or comp, not good. Usually, it is 30 to 50 yards downrange, at least initially.

[CarRacer]

Alright, so the 55gr Hornady are out. I'd rather not roll the dice on a bullet that might or might not work.

Where should I look next? 69gr Noslers?

[MarkCO]

69 or 77 Noslers or Sierras, 68 or 75 Hornady's. I like 69 Noslers, but I use a 1:8 barrel for 3Gun.

Realize that the "cost" of bullets through a barrel exceeds the cost of the barrel by a pretty large margin. I shoot what I want and get a new barrel when needed.

[latech15]

I like the sierra 69's but occasionally you can find the hornady 68's for a few dollars cheaper/100. They shoot really well too.

[bushmeat]

Shooting 69s at paper at 25 yards is a bloody waste of money. Shoot the 69s for 200 yards and out and use the 55s for everything else.

[RePete]

I run a 16" 1:7 twist barrel and 45gr - 62gr bullets without accuracy problems.

A friend run 45gr Winchester ammo through his 10" without issue. Accurate at 100yds, with his shooting.