OzFclass

G,day.

Purchased the Hornady Oal guage. Purchased the special .308 case. Tried to set up the berger 155.5 just off the lands on my recently purchased Omark 44B with heavy barrel. (Assumed it is an original heavy barrel from Omark) The bullet when touching the lands is out of the case.
Why did they bother to make this TARGET rifle, with a 1:14 twist, to shoot 144 grain projectiles, and you cant set it up to position projectiles just off the lands?

Puzzling I think, as the twist doesn't allow heavier / longer projectiles. Any ideas?

cheers

Leadlauncher

Any idea how many rounds the barrel has fired?

No Danny, but I am guessing it is in the thousands. The muzzle end looks a "bit" worn. But what will that have to do with the chamber length?

cheers

leadlauncher

The special .308 you got from Hornady is a generic case.It's better to have one fired in your own rifle(not fl resized).It could be the problem.Anybody with a lathe can cut the thread for you.It's worth a try.Also as Danny said,the barrel is overchambered or worn out.
Peter

Shot one or three of those barrels out. The didn't come from the factory with excessively long throats.

I suggest that you get somebody with a bore scope to have a look at the throat wear, if there is such a person your neck of the woods.

Earlier on I used the bought cases for my Stoney Point (now Hornady). Now I make my own. I found the Stoney Point cases could differ by around 5thou from a case fired in my rifles and measured to the datum point on the shoulder. That in itself was not a problem as I just factored in the difference. So, I don't think the difference between your purchased Hornady case and your chamber is going to be the solution to your issue. I would also suggest as per JohnK that your throat has "advanced" somewhat. I have found, aside from ending up with a measurement that requires the projectile to be virtually not seated at all into the case, that with the throat eroded badly you get a different reading each time you do the test. You can feel the roughness when you push the projectile fwd into the lands and it depends upon how hard you push how far the projectile goes through the roughness.

I wasn't around when these things were new,but in my opinion,they were given a NATO chamber,and given the ravages of time,the throat has probably increased as well.What I would do is load a stiff load with a good length of bullet grip in the neck and ignore the bullet jump and get on with it.There is a fair chance that it will shoot quite well.If it doesn't,you will need to re barrel,nothing lost.The current idea of tight chambers,tight throats and no bullet jump = tight groups!is not always correct.

leadlauncher wrote:No Danny, but I am guessing it is in the thousands. The muzzle end looks a "bit" worn. But what will that have to do with the chamber length?

cheers

leadlauncher

I would take an educated guess that your barrel is shot out. the Hornady OAL gauge is designed to measure throat length, not chamber length. You cannot "find" the lands because the throat has eroded forward. One of the purposes of the OAL gauge is to check throat erosion. I use one regularly when cutting custom throats.
Keith H.

Until you get a new barrel sorted or this one rechambered, try some HBC 155 grn projectiles. They seat in the case a fare bit further than the bergers do. You should be able to find a reasonable AOL.

When I started shooting and reloading around twenty years ago I purchased an Omark from retiring shooter in our club and faced the same problem, I asked Bill Hallam who was here at the time,as he had checked out the rifle with a bore scope, and was told dont worry about seating bullets out to touch, just make sure your loaded ammo is straight. Even to this day I dont worry about OAL in Omarks when trying them out, you will soon see if the barrel is buggered when you shoot your first group. They either work or they dont!

Thank you all for your advice. I will try some HBC at say a seating depth for Sierra Palma ? Herewith photo of a group of 168 Sierra's at 100 yds.

cheers

Leadlauncher