Ever had a rifle not like ammo?

I have a DiamondBack .223 with a 1:8 twist barrel that I use for hog hunting. Tried to sight in the Hornady Black .75 grain and couldn't get it sighted in. One round would be high/left and the second, without any scope adjustment, would be low/right. Very frustrating! Tried multiple boxes of the same ammo just to make sure that it wasn't a bad box, and got the same results. Switched back to my regular ammo, Hornady .223 58 grain, and got it sighted in with 2 shots. I've never had a rifle not like ammo like this before. Hornady's ammo is my favorite and I've killed lots of hogs with it but my rifle didn't like the Hornady Black 75 grain. Like I said, this has never happened to me before, anybody out there with a similar experience of a rifle not liking a certain type of ammo? My buddy has a .223, different make but same barrel twist and his rifle shoots it just fine.. that's the most frustrating part of the whole ordeal..

Yes

When I first purchased my Browning A-bolt in 270 I got a box of Core-lokt and went to the range. I could not get these rounds to group worth a dang and sure couldn't zero it. Bought a box of Federal Fusion 150 gr and zeroed in 3 shots and had a group smaller than an inch at 100 yds.

My Yugoslavian SKS will not properly chamber anything but the cheapest steel case ammo. I learned quickly that those old Eastern European firearms weren't made to shoot quality brass case ammo.

Well good, then I'm not the only one.. I had myself convinced that my thermal scope was broke or something..

Yes, I've seen it many times. Factory ammo is loaded on large progressive machines and the powder is dispensed out by volume (not weighed). You will get a large powder charge variation this way, often times in the 1 to 1.5 grain spread. I have seen as high as a 2 grain spread on some magnum ammo. This causes 2 main problems.

1- the large powder charge variation takes you in and out of any possible accuracy node. When I test a rifle for load work up, I vary the powder charges in .3 or .4 grain increments. Load A would be, say 44.0 grains of powder, Load B 44.3 grains, Load C 44.6, Load D 44.9, etc. I am dialing in the ammo to the rifle in this manner. If your factory ammo has a spread of AT LEAST 1 to 1.5 grains spread, you are covering multiple accuracy nodes in one ammo lot and it's causing large spreads in the consistency of the ammo. This boils down to open groups, POI shifts, and poor consistency.

2- the larger powder variation will cause a high extreme spread on velocity, effecting the point of impacts, and inconsistent groups at longer ranges. Most factory ammo will be in the 50-100 fps extreme spread, sometimes more.

But, if a rifle shoots a certain bullet really bad, it doesn't mean that the rifle doesn't like that bullet. It means that the rifle does not like the load used with that bullet (meaning the powder and powder charge). For example, I had a customer who wanted to shoot the 180 grain Accubond out of his 300 WM. He tried several factory loads, and nothing shot good. He called me for load work up and said, let's not use this bullet, since my rifle does not like this bullet. That's false. What your rifle didn't like was the factory load used with your rifle. We selected this bullet for load work up, and that rifle ended up shooting that bullet very well.

Also consider your caliber you are shooting. I have seen 223 ammo shoot night and day different in various rifles. I have 2 AR-15's, both in 223. One is a cheap $750 rifle, and the other was a high end match upper. I dialed in a load with a 60 grain V-max in the cheap AR. It shot about 3/4" to 1". Not bad, I'll take it. I loaded up a bunch of that ammo. Later, I tried the 60 grain V-max ammo in my custom upper, and it shot about 4"-5" groups at 100, and it was very random. I thought something was broken or going wrong. So, I started over, and changed up the powder and loaded some test loads with the same 60 grain V-max, just with a different powder. It shot amazingly better, and one of the loads shot 1 ragged hole at 100. For S&G, I tried the other 60 grain V-max ammo, and same bad groups. So, how does 1 high end rifle shoot the exact same bullet (seated to the same seating depth) so bad with 1 load, and the other load shoot bug holes? It's a mystery to me!

I have seen 223 being one of the worst calibers for this large variation in accuracy. Change something up, and it could get better.

75grn is a big bullet for a .223. since its a small diameter it means the bullet is long/longer than normal. rifles with a fast rate of twist meant for shooting small bullets will not do well with longer heavy for caliber bullets. standard load for a .223 is a 40-50grn bullet. imagine doubling that weight the bullet would be approaching twice as long.

I have a Remington .223 and shoot some 60grn nosler partition thru it. they shoot well, and the partition gives the performance one would expect to get by go to a larger bullet. you probably need to experiment a bit with what is the largest grain bullet the rifle will accept and then see what options you have for that bullet size.

Sorry, but this is 100% incorrect (on the twist and stability part). Yes, 75 grain is a heavier and longer bullet. But in a 1:8" twist, this 75 grain BTHP Hornady bullet will be adequately stable. Rifles with a faster twist are designed to shoot the longer/heavier bullets, that's why they have the faster twist. A lighter/shorter bullet requires less twist to stabilize, so they tend to work in a 1:12" or 1:9" twist.

Id bet there is more 55 and 62 Grain 223/556 than any other grain.

unless you have some sort of special match/target grade rifle that is meant for shooting heavier match grade bullets I would think most .223 have a faster rate of twist meant for shoot small/short bullets. 60grn will probably be your threshold for accuracy if you did well with the 58grn, no reason the 60 shouldn't be ok as well.

a larger bore rifle like a .270 or .30 cal or larger has a slower rate of twist to accommodate a larger bullet. I believe twist rate of 1:8 means there is a complete turn of the rifling for every 8in of barrel. its tighter because it has to be to put any traction on a small bullet. larger bullets are more flexible on variety of bullet weight. my brother shot loads in a .270 from a 90grn load to a 150 and at 100yds all were near the bull.

I have a .54 cal hawken muzzleloader that has a 1:60 rate of twist, the barrel is not 60in long, so it never makes a full turn, but the bullet is huge.

That's all good info, thanks. I just got some Maker .223 62 grain and I'm going to try that out next..

The military shoots 62 grain in a 1/7 right hand twist accurately out to 300 meters and capable of further. Almost all bulk ammo is 55gr or 62gr and they both shoot very well in a 1/7.

if you know for sure you are probably right. I just know bullet size and rate of twist can make a difference.

Was in the Army for almost 12 yrs I'm positive.

Here's a little bit of info. Do you know why the military went to a 1:7" twist? ..... NATO specified the type of bullets that can and can not be used. Early models of AR-15's ran 1:12", and some were 1:9" twists. The terminal performance (what happens internally when a bullet enters soft tissue) was not that great. We found out if you go to a 1:7" twist and spin the bullet fast, the RPM's go way up. A bullet fired out of the 7" twist barrels enter soft tissue, and the rotational force causes the bullet to yaw, then tumble or fragment. This extra spin allows even an FMJ bullet to yaw and tumble and be more effective for better terminal performance.

and that's how you get around not being able to use hollow points or any type of bullet that expands

^^^ Exactly!!! Sometimes the military does do it right!!! I guess when it comes to killing sh%t, they got that down!

Very true..

50Cal API now that will keel.

Oh heck yeah

I'm a bit surprised that there has been no discussion about barrel harmonics. I'm a reloader and have several Ruger #1's that I tried to get to shoot inside a barn at 100 yards without much luck. Finally, in frustration, having tried all the published tricks of the trade to "fix" the problems, I bought a little rubber "doughnut" that slides onto the barrel. Moving the doughnut up or back in small increments, and CHANGING NOTHING ELSE in my loads, I started getting MOA out of 3 of the 4 rifles! I assume that the doughnut is a workaround for a more serious, bedding problem, but it worked well for me, and I think it must be a harmonics issue with the barrels that is dampened or changed by the rubber ring.

1/8 is about the perfect twist, 1/7 is really only need to spin longer than mag length target loads typically. If it will fit into a mag, a 1/8 will probably spin it just fine.

As far as yaw, a slower twist rate will yaw and become unstable quicker than the tighter twist , however it was abandoned with the adoption of heavier bullets and the longer tracer ammo that is used with it. However, a tighter twist rate increases fragmentation of the projectile much better and that increases its effectiveness.

As to the OP questions: Many stock rifles will have a preference for a particular load, a barrel that will shoot many loads well is harder to find.

I’d scrap a rifle barrel before I put that abomination on anything, even if it does work.

To each his own. I, personally, couldn't afford to replace the rifle barrels.

[quote=Erich]unless you have some sort of special match/target grade rifle that is meant for shooting heavier match grade bullets I would think most .223 have a faster rate of twist meant for shoot small/short bullets. 60grn will probably be your threshold for accuracy if you did well with the 58grn, no reason the 60 shouldn't be ok as well.

a larger bore rifle like a .270 or .30 cal or larger has a slower rate of twist to accommodate a larger bullet. I believe twist rate of 1:8 means there is a complete turn of the rifling for every 8in of barrel. its tighter because it has to be to put any traction on a small bullet. larger bullets are more flexible on variety of bullet weight. my brother shot loads in a .270 from a 90grn load to a 150 and at 100yds all were near the bull.

I have a .54 cal hawken muzzleloader that has a 1:60 rate of twist, the barrel is not 60in long, so it never makes a full turn, but the bullet is huge. [/quote) listen to Chad, you are totally wrong about fast twist barrels, only the past few years did mfg's start production with faster twist, the first ar I had wouldn't shoot anything over 55gr, my latest one I shoot 75gr with amazing results

Neither can I. That’s how awful I think they look.

Say what?

I have a core diamondback, hvy barrel, 1:8 twist. it hates 77 gr. 5.56, loves the 62 gr. green tip.

just got some 65 gr. hpbt to try, probably will just stick with the 62 gr. tho.

From what I understand, they went with the 1:7 twist in order to stabilize the heavier and longer M856 tracer round despite increasing group size with standard M855 which was more accurate out of a 1:9 barrel.


https://www.americanrifleman.org/article...ball-cartridge/

I have a Ruger 1 22-250 and I can't even get it on the paper using Hornady, but I can drive tacks with Winchester Ballistic SilverTip ammo.
First gun I've ever seen that just doesn't like some ammo.

It's been frustrating. Just finally gave up and dropped down to smaller grain ammo..

My Glenfield 30A in 30-30 shoots 150gr bullets very well and accurate. Generally can touch each 5 shot group with a quarter at 100 yards with 150gr. But 170gr targets look like I shot them with a shotgun at the end of a session- all over the place (as much as a 10 inch spread in shots). Same brands- only difference is bullet weight.

As ChadTGR42 said, this cal can go from tackdriver to pieplate with an ammo change.
Part of the reason .223/5.56 are all over the place is because THEY ARE.

First, you have two loads: .223 at one pressure and 5.56 at considerably higher pressure.
Second, you have 3 chambers readily available: standard .223, .223 Wylde and 5.56.
Third, there are twist rates between 1/6 and 1/13.
Forth, gas tube length/bolt weight.
And finally, multiple rifling versions.