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Posted: 10/25/2012 6:09:46 PM EDT
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Will keyholing ammo cause damage to the barrel in any way?
Getting a few rounds that keyhole at 25 yards out of a new barrel/gun. Winchester ranger 556 m855 |
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Are you shooting any reloads? Reason I ask - I was shooting with a friend and his dear rifle was shooting old reloads that his dad had loaded hot. The brass was bulged and cracked. He could hardly get on paper at 25 yards. When he did, it key hold. That is when we checked the brass.
As far as your barrel, I do not know. I cannot see how it could be good for it, but I do not know about actual damage. Wish I could be more help. |
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Is the keyhole completely sideways or just a little? Perhaps the round is impacting the paper with a low angle of attack as seen at the link?
Why not M855/M193? |
| Check with a gun smith about the barrel. Unless it is over pressure (and it can't be if you are shooting m855) or something wrong in the chamber, it has got to be the barrel. 25 yards is nothing as far as distance, and a key hole puch (even a couple of times out of 50) make me wary of the firearm. Have you tried to shoot it past 25 yards and can you get on paper at 100 yards? |
| Thanks guys for all the input. Your answers got me worried so i ran to the range after work today. Figured I try to get some pics of the problem. Setup at the same distance and started banging away. Forgot the bipod, so just used the camelback for a rest. Anyway, had nothing but good results this time around. Shot 60 rounds into cardboard and all straight impacts. No keyholing at all. Tryed PCM xtac and bha 60g vmax and they were great, straight as a laser. So I'm wondering what might have caused this the last time around. Maybe just a couple bad rounds? The way I was shooting? Kinda stumped. But I am kinda relieved, was worried the case of whinny ranger was fukd. |
Good thought. Happened to me once, and drove me crazy trying to figure how I got some oddball flyers when I knew I was pretty close to dead on. Sure enough, the guy at the bench next to me let his son shoot, but never told him which targets were his. The kid wound up shooting at mine. 
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Quoted:
May i hijack this thread really quick? Dont look at the groups, they are terrible i know. My hand loads do not do this. Hand loads are Hornady 55grSP/c over 35.8TAC with WOLF primers. Ammo in question is WOLF 55gr in a LMT 10.5'' sbr with 1/7 twist upper. http://i1244.photobucket.com/albums/gg575/pumbaajk/IMAG0163.jpg Shouldn't be happening with that barrel/ammo combination. Might be a bad lot of Wolf. Of course, if you're really using 35.8gr of TAC under a 55gr bullet, your rifle has probably exploded already. 
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I think the only way that a bullet can keyhole 25 yards from a barrel is it is not spin stabilized at all or the crown of the barrel is in shambles. You can test for the first by pulling a bullet and measuring its diameter, it should be 224”. The second potential problem can be tested by firing different ammunition. Since you said that it only does this with Win ranger m855, I would say that the bullet diameter is undersized. Undersized bullets will not engage the rifling and so is not stabilized and it will then keyhole. It's as simple as that. |
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Quoted:
Quoted:
May i hijack this thread really quick? Dont look at the groups, they are terrible i know. My hand loads do not do this. Hand loads are Hornady 55grSP/c over 35.8TAC with WOLF primers. Ammo in question is WOLF 55gr in a LMT 10.5'' sbr with 1/7 twist upper. http://i1244.photobucket.com/albums/gg575/pumbaajk/IMAG0163.jpg Shouldn't be happening with that barrel/ammo combination. Might be a bad lot of Wolf. Of course, if you're really using 35.8gr of TAC under a 55gr bullet, your rifle has probably exploded already. I am sorry. 25.8TAC is what I meant. Typing from a phone sucks! |
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Quoted:
Pumbaajk Try taking a look at the crown on the barrel. Is it only with the wolf that the key holing occurs with? It may be just the ammo. But like everyone suggests can you measure the ammo to check its diameter. I am not saying its not the crown but this upper has less that 200 rounds through it. Would this ammo be doing the same thing out of a 16" barrel? I ran this ammo in a rifle operator class and took it out to 400 yards accurately. |
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Quoted:
Quoted:
May i hijack this thread really quick? Dont look at the groups, they are terrible i know. My hand loads do not do this. Hand loads are Hornady 55grSP/c over 35.8TAC with WOLF primers. Ammo in question is WOLF 55gr in a LMT 10.5'' sbr with 1/7 twist upper. http://i1244.photobucket.com/albums/gg575/pumbaajk/IMAG0163.jpg Shouldn't be happening with that barrel/ammo combination. Might be a bad lot of Wolf. Of course, if you're really using 35.8gr of TAC under a 55gr bullet, your rifle has probably exploded already. Yea man 35.8 of TAC is SMOKING!!! |
| Update: With the short barrel(10.5) and low velocities of the Wolf ammo, my barrel would not stabilize it. I ran up some hand loads and tested again and with propper velocity, 55grs with aything from 23.5-26.2TAC shoots fine. Anything below started to show signs of instability. |
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