Range Report .223 Keyholing
- Thread starter Boatninja
- Start date
How many rounds on it? Last time I shot out a barrel it started showing up in the heavier bullets first.
How does the rifle shoot lighter bullets?
I would personally question the barrel as I feel any normal 1-9 barrel should absolutely shoot 69/70 grain bullets and occasionally the do decent with 75/77’s.
New gun, just hoping it’s a dummy thing’. I have done all the basic stuff, retourqued everything etc, going back to dealer tomorrow, they will make it right, good guys.
ce the question amigo.
Hen
Hence the question amigo.
ce the question amigo.
Will be going back to gun shop tomorrow, they are good guys. I just think a Kimber Longmaster classic shou;d shoot any factory ammo without keyholing at the very least
Would not be the first time a factory worker got barrels engraved wrong.
I would bet its a defect that was missed in qc.
7, 8, or 9 twist would all work, can't say about twists I haven't owned.
I like 8 twist for 16 inch , 7 for sbr.
I expect longer barrels need less twist to stablize in general
or is it weight of bullet only that matters?
Can you actually over twist a round?
I would bet its a defect that was missed in qc.
7, 8, or 9 twist would all work, can't say about twists I haven't owned.
I like 8 twist for 16 inch , 7 for sbr.
I expect longer barrels need less twist to stablize in general
or is it weight of bullet only that matters?
Can you actually over twist a round?
Looks like the jackets were compromised from overly aggressive twist rate and were spewing the lead core out.
Youre seeing the bullets spinning so fast they are startng to rupture and slinging lead out the bodies
Thanks for confirming that.
I would guess that fps effects this as well.
I did a lot of experimenting with subsonic, but not much on pushing the fps
race the other direction.
I stay at the best grouping just under published max, call me timid or worse
but the extra 50-100 fps will not blow my day since I'm not competitive.
My brass and gear will last longer I figure.
I have friends burning 2+ barrels a year in thier wildcat stuff.
I would guess that fps effects this as well.
I did a lot of experimenting with subsonic, but not much on pushing the fps
race the other direction.
I stay at the best grouping just under published max, call me timid or worse
but the extra 50-100 fps will not blow my day since I'm not competitive.
My brass and gear will last longer I figure.
I have friends burning 2+ barrels a year in thier wildcat stuff.
Very much so
Bullet RPM = MV X 720/Twist Rate (in inches)
Calculating Bullet RPM — Spin Rates and Stability « Daily Bulletin
Most serious shooters can tell you the muzzle velocity (MV) of their ammunition, based on measurements taken with a chronograph, or listed from a manufacturer's data sheet. (Of course, actual speed tests conducted with YOUR gun will be more reliable.) <img src=http://accurateshooter.
Its not just a queef if something comes out leaving a mark... even the hottest squirt is still piss
Those bullets showered the target with love!Its not just a queef if something comes out leaving a mark... even the hottest squirt is still piss
That is the MAIN Problem with over spinning stuff today which is being promoted.
They guys promoting it are using short barrels with reduced velocity, those trying to copy it use longer barrels with more velocity and then they start to see fliers and can't figure out why the latest and greatest doesn't work. (See 300NM with an 8 Twist)
The don't always come apart but they can deform under the jacket and get out of balance, hence the fliers. Some bad, other worse, the degree of the deformation can vary, but the results are usually the same, lack of consistency.
They guys promoting it are using short barrels with reduced velocity, those trying to copy it use longer barrels with more velocity and then they start to see fliers and can't figure out why the latest and greatest doesn't work. (See 300NM with an 8 Twist)
The don't always come apart but they can deform under the jacket and get out of balance, hence the fliers. Some bad, other worse, the degree of the deformation can vary, but the results are usually the same, lack of consistency.
If they are key holing they might not have enough velocity.
If you are spinning 69 grainer so fast that they are blowing up, then you need one of two things...
1... reduce the velocity if you are a hand loader.
2,,, get better bullets.
I've been running 69 grain SMKs in a 1:7 with 26 grains of W748 since 1985 without a problem. Developed that load for my AR15A2 Delta HBAR, hot stuff at the time.
I like this pairing because the fast rotation jacks up the explosives impacts, but its just under the ragged edge of self destruction so its accurate.
Years back I was running 115 Bergers out of my 6x47 Lapua for F-Class and had a bad day where a few blew up in flight during a match. Berger continued to produce that bullet but started calling it a hunting bullet instead of match. Then they started using thicker jackets for the Match version. I was running 3000 FPS with 1:8 twist.
If you are spinning 69 grainer so fast that they are blowing up, then you need one of two things...
1... reduce the velocity if you are a hand loader.
2,,, get better bullets.
I've been running 69 grain SMKs in a 1:7 with 26 grains of W748 since 1985 without a problem. Developed that load for my AR15A2 Delta HBAR, hot stuff at the time.
I like this pairing because the fast rotation jacks up the explosives impacts, but its just under the ragged edge of self destruction so its accurate.
Years back I was running 115 Bergers out of my 6x47 Lapua for F-Class and had a bad day where a few blew up in flight during a match. Berger continued to produce that bullet but started calling it a hunting bullet instead of match. Then they started using thicker jackets for the Match version. I was running 3000 FPS with 1:8 twist.
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