Keyholing bullets
I purchased 1000 9mm reloads from a reputable distributor (not the reloader). Bullets are hard cast lead flat point,122 grains, made by Bull-X. Bullets have two driving bands and a single grease groove filled with a blue lubricant. Bullets mike 0.355" and show no base deformaties.
Loads look good but they keyhole. Not just from one gun but from every 9mm I have fired them out of. Most are sideways at 5 yards.
No lead buildup in barrel.
Have not recovered any of the bullets as they go into a steel backstop.
Why the keyholing? I thoght nominal diameter of 9mm bullets is 0.355".
Loads look good but they keyhole. Not just from one gun but from every 9mm I have fired them out of. Most are sideways at 5 yards.
No lead buildup in barrel.
Have not recovered any of the bullets as they go into a steel backstop.
Why the keyholing? I thoght nominal diameter of 9mm bullets is 0.355".
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The lead may be too soft. Although you'd expect to get lead build up it may just be deforming the lead and not taking the rifling. To get keyholing you'd either have to have a lack of gyroscopic stability (spin) or imbalance.
Love them Beavers
Keeping the "Hairy League" in check since 19480 -
Set up a big piece of paper about 10yds from the muzzle and shoot through it. If you're getting multiple holes then you probably have deformation occuring and the rifling bands are stripping
Love them Beavers
Keeping the "Hairy League" in check since 19480 -
Hi,
I had that problem with some of my handloads one time.
The particular load was a new recipe I had never used before and it was a light target load for 45 ACP. At the range, each shot went through the paper target sideways.
The only element of pistol and cartridge combination that was untested was the reload itself, i.e., the powder charge. I had used the same batch of lead bullets as before, the primers were of the previously used lot, the pistol fired well with rounds other than the reloads.
The problem turned out to be the powder charge was too light. After increasing the powder charge a few tens of a grain the bullets quit keyholing.
If these 9mm reloads that you purchased have been loaded on the light side, this may be one possible explaination for the keyholing. Light loads can also cause a bullet to not have sufficent velocity to spiral fast enough to stabilize the bullet.
Regards,
Heavyiron
"If I don't see you nomore on this world, I'll meet you on the next one, and don't be late!" - Jimi Hendrix0 -
If you are reloadind lead it should be a .356, jacketed .355 the lead is to soft and is not picking up enough of the rifling.
Down Zero0 -
Two subjective observations:
1) Lead appears to be hard, certainly not the dead soft of a muzzle loading ball. Can't scratch it with my thumbnail and is fairly resistant to scratching with a jeweler's screwdriver. Is it possible that it is not upsetting enough to take the rifling because it is tooo hard?
2) I have fired about half a dozen different commercial loads and one other handload though the gun I am using now. Again, my obserrvation is subjective but I can tell no difference between this load and all others with the exception of a Remington loading which seems hotter and certainly has more muzzle flash.
Thanks goodness I have only 230 more rounds to use up. I am using it in a defensive pistol course where target accuracy is not needed.0 -
The other possibility is that it is too hard and the pressure is too low. Lead bullets hardness needs to be matched to the pressure level of the load in order to "obturate" to fit the bore perfectly. If pressure is too low with a hard bullet, you will get excessive blowby and poor accuracy.
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If the 9MM's are glocks they will not stabilize lead bullets due to the shape of the rifling. The .355 size may not inpart enough engraving force and the bullets may be tumbling due to lack of spin; but I would expect to see some leading.
My Taurus 9MM will keyhole lead bullets no matter what design, Since the 9MM is just a blasting plinker, I really don't care. It does not do that with jacketed bullets.0 -
The advice you have received is essentially quite good. The fact that it occurs with other guns indicates that it is tha ammo at fault, not your pistol. I do not, however think that the .355 is the problem (even though that is slightly undersized for the 9 mm) When the cartridge fires, the soft lead bullet will swage up to the bore size, so a few thousanths are not that critical. One factor has not been considered; that is overall length. If the bullet is a significant distance from the lands, the jump through the unintended freebore will do two things. First, this may create a loss of pressure problem, since freebore relieves pressure. Second is the most important: that SHORT bullet may well tip prior to engaging the rifling, and could leave the bbl in an unstable manner. This freebore-caused tipping does not occur with longer bullets but is potentially quite a problem with short ones.
Good luck
Morty0
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