Shooting issue

[Northwoods]

Took thing 2 to the range yesterday to get sighted in for hunting season.  Ammo choices are rather sparse, so for the .270Win all I could get was Browning lead free 130gr.  I’d prefer to hand load but time is short, and supplies have been hard to come by for a while anyway.

Anyway, at 100 yards it seemed to be performing pretty well.  Rifle is a 50’s or 60’s era JC Higgins bolt action.  1-1.5” groups without really trying all that hard.  200 yards was another matter.  The other 2 center fire rifles (both CZ-550s) did fine at 200 yards.  The 9.3mm was about 1.5” groups at 200.  That .270 though I got like 3 shots to hit the paper out of probably 15+ rounds.  I tried everything to figure where they were going.  The target boards were large enough for 3 targets across with 2 rows.  I aimed at the top of the board, bottom of the board, left column, right column, dead center between the 2 middle targets, etc just to see where the rounds were going.  Went back to 100 yards and the bullets were hitting basically POA.  Back to 200, no holes in the paper again.  Did that a couple times.  Shot the other rifles at 100 and 200 with good predicable groups.  Back to the .270 and still couldn’t find holes.

Could the bullets be keyholing between 100 and 200 yards?  The 3 holes I did find didn’t look at all like the bullets were keyholing.  What else could cause that?  Didn’t have a chronograph but based on felt recoil I’d believe 3000fps (3100fps advertised on the box). 

[French G.]

Gotta be barely stabilized an going off somewhere. Should only be about only 3" of drop max with a 100 yard zero right? Worn out barrel, or some older slow twist?

What is the 9.3? Sounds interesting.

[Northwoods]

9.3x62mm Mauser.  It’s basically a .36 caliber in a slightly longer case than a .30-06.  With 286gr bullets I’m getting 2400fps.  Taken 3 elk with it.  First was a standing off-hand shot at maybe 20 yards on a big AZ cow elk.  Took 5-6 steps and face-planted.  Got a 4x4 bull on the WA coast at 240 yards.  Pole-axed that one.  Got another cow elk at 220 yards.  She died in a mud hole less that 10 yards from where was hit.

Originally got that rifle because I had an invite to hunt in South Africa about 15 years ago.  Never went, but figured that caliber would give me half a chance if a dangerous game animal threatened me.  Not that I’d purposely target DG with that rifle but sometimes you get surprised.  It’s become my dedicated elk rifle (and hopefully eventually gets used on moose).

[Hawkmoon]

Could the bullets be keyholing between 100 and 200 yards?  The 3 holes I did find didn’t look at all like the bullets were keyholing.  What else could cause that?  Didn’t have a chronograph but based on felt recoil I’d believe 3000fps (3100fps advertised on the box).

Keyholing should still leave holes.

Velocity? At what distance will the rounds drop out of supersonic? Is it possible that they get enough wobble as they cross the threshold that they blow up?

Try shooting intermediate distances -- 125, 150 175 yards.

[Northwoods]

Keyholing should still leave holes.

Velocity? At what distance will the rounds drop out of supersonic? Is it possible that they get enough wobble as they cross the threshold that they blow up?

Try shooting intermediate distances -- 125, 150 175 yards.

If it anywhere close to 3000fps at the muzzle it should stay supersonic to well past 1000 yards.  To transition between 100 and 200 either something is very wrong, or it’s starting out barely supersonic at the muzzle (speed of sound is +-1100fps depending on conditions).

[Ben]

If it anywhere close to 3000fps at the muzzle it should stay supersonic to well past 1000 yards.  To transition between 100 and 200 either something is very wrong, or it’s starting out barely supersonic at the muzzle (speed of sound is +-1100fps depending on conditions).

Still, something is obviously happening between 100 and 200, so I would reiterate Hawkmoon's advice. Move out (or perhaps move back) 25 yards at a time to see if you can collect some evidence.

Also, do you have a sled or other support to lock in the rifle, or are you just resting it? What sight does it have on it?

[French G.]

Pretty nice gun on the 9.3, sounds like something I need. I was hoping it was x62. I have heard of people hunting on this continent with a 9.3x74 and that may be a bit much. I want them all, right now I have the most obsolete one, 9.3x72.

[HankB]

These are solid alloy (no lead) polymer tipped bullets, right?

OK, so they don't have a jacket that's coming apart downrange like you sometimes see with varmint bullets that are driven too fast.

They're grouping decently at 100 yards, so they must be fundamentally sound. (Solid alloy Barnes-X bullets threw occasional "flyers" for me - but only about 80% flew true at 100 yards. ALL of them are grouping well for you at that distance.)

That leaves the polymer tip . . . I wonder if something is melting or coming loose and destabilizing the bullet somewhere between 100 and 200 yards. If the polymer just flattens out a little it probably won't make too much distance as accuracy isn't as dependent on nose defects as base defects, but if the polymer is being shed or flopping over on the side, I could see it diverting the bullet.

Stability could be an issue, too - 130 grain bullets have been the "standard" for .270s since the round was introduced, but "lead free" bullets will be a little longer than traditional "cup and core" bullets and maybe they're not being stabilized. But shooting well at 100 and going totally wild - to the point of missing the paper entirely - at 200 is pretty extreme.

[griz]

My suspicion, and it's only a suspicion, is that the copper bullets are too long to fully stabilized out of that barrel.  It is weird that it would just go all over that map between 100 and 200, but the answer is what Hawkmoon suggested, shoot at the middle distance.

[MechAg94]

The closest thing I have seen is with a suppressor that is not aligned very well.  The bullets were not impacting the suppressor, but it was enough they were way off at 100 yards.  Still okay at 25 yards.  Realized later the thread adapter was not as tight on the threads as it should be allowing a bit of slop.

[Northwoods]

Still, something is obviously happening between 100 and 200, so I would reiterate Hawkmoon's advice. Move out (or perhaps move back) 25 yards at a time to see if you can collect some evidence.

Also, do you have a sled or other support to lock in the rifle, or are you just resting it? What sight does it have on it?

I was using the sandbags provided by the range.  Gun was very solidly held for the shots.  Gun is wearing a fixed 4x scope.  Unsure on brand without looking at it.

I’d have to go to a different range to test 125, 150, etc yard distances.  That range has 50, 100, 200 and 300 yard targets, and I can’t even go out and collect my own paper, let alone move target stands.  They call cease fires every few hours and staple up new targets for everyone.

[Northwoods]

These are solid alloy (no lead) polymer tipped bullets, right?

Yes.

[Northwoods]

Pretty nice gun on the 9.3, sounds like something I need. I was hoping it was x62. I have heard of people hunting on this continent with a 9.3x74 and that may be a bit much. I want them all, right now I have the most obsolete one, 9.3x72.

I love that rifle.  It’s got the hogsback style stock.  If it didn’t recoil so much it would be my favorite rifle.  But 10 rounds off a bench rest and I’m borderline bruised.  Probably should at least get a better recoil pad.  Don’t really want to put a break on it, partly because that would require removing the iron sights.

I’ve got a few English walnut logs that have been given to me.  I’m thinking of milling at least one of the slabs thick enough for making a gunstock.  Not sure how thick that would be, but probably 4” would be a good amount.  Basically copy the stock on my 9.3x62, but inlet it for my 6.5x55.  Or any other hunting rifle I might eventually own. 

[charby]

I had something similar happen to me, ended up being the scope internals were damaged. New scope and the problems went away.

[Northwoods]

I had something similar happen to me, ended up being the scope internals were damaged. New scope and the problems went away.

I’ve got some older scopes I’ve taken off when upgrading laying around.  I’ll try putting one of them on and see what happens.  Likely won’t have time for that until after hunting season is over unfortunately.

[Ben]

I’d have to go to a different range to test 125, 150, etc yard distances.  That range has 50, 100, 200 and 300 yard targets, and I can’t even go out and collect my own paper, let alone move target stands.  They call cease fires every few hours and staple up new targets for everyone.

No offense, but that's one crappy gun range.

[Jim147]

Has this rifle always shot cup and core bullets well?

[Northwoods]

No offense, but that's one crappy gun range.

It’s county run.  The pistol and smallbore range is very different.  Just the highpower rifle line that’s like that.

Unfortunately there’s few alternatives without a substantially longer drive, and it’s 30 minutes already to that one.

[WLJ]

My guess is that the twist rate of the barrel isn't fast enough to adequately stabilize bullets of that weight and it not showing up until the bullet drops below a certain vel. Try a lighter bullet and see what happens.

[Northwoods]

My guess is that the twist rate of the barrel isn't tight enough to adequately stabilize the bullets of that weight. Try a lighter bullet and see what happens.

Ever seen a factory .270 Win load under 130gr?  I haven’t.  They probably exist, just never seen it.  It shoots 150gr Remington Core-locks just fine at 200 yards (or did a few years ago). 

[WLJ]

Ever seen a factory .270 Win load under 130gr?  I haven’t.  They probably exist, just never seen it.  It shoots 150gr Remington Core-locks just fine at 200 yards (or did a few years ago).

Got it in my head the issue was with the 9.3 

My other guesses are undersized bullets not engaging the rifling property or worn out rifling.

[Jim147]

What do you need to be able to roll your own?

[Northwoods]

What do you need to be able to roll your own?

Besides time (considering it takes a few trips to range to dial in a good load)?  A suitable powder and projectiles.  I haven’t researched the good powders for the .270 so it’s possible that one I’ve rejected for other calibers would work.  I think I have the dies, definitely have a sizing die, need to look but should have a seating die too.  Definitely have brass.  Primers are getting pretty low, but I’ve got enough for now.