chamfering vs lyman M die

[Juma]

Until we used the M die we found huge shavings on the Barnes projectiles because of that long monolithic bullet.The gentle flaring of the case mouth with the M die and viola the problem disappeared.

 

[snakepit]

The Lyman's web site says the Rifle Neck M Dies are a "Must Have" for Cast Bullets or Flat Base Bullets. Does that mean they are not required or as important for Boat Tail Bullets?

 

[CatShooter]

The Lyman's web site says the Rifle Neck M Dies are a "Must Have" for Cast Bullets or Flat Base Bullets. Does that mean they are not required or as important for Boat Tail Bullets?

No, that does not mean that - the small flair on the case mouth keeps the case from scoring the bullet jacket, no matter what the base is.

 

[Patch700]

How much of a difference does visual scratches on the jacket actually affect downrange performance?

I had approx. 60 bullets given back to me by a fellow shooter who bought a 100 count box of 139 lapua scenario OTM'S from me (same lot# as mine as I had bought 30 100 count boxes at once)

They were pulled using a forster collet puller and did show very slight signs such as scratches along the bearing surface.. I used those bullets at a later date and found them to go rite where the new ones printed (600 yds)

I guess what I'm saying is if your brass is stripping enough of the jacket off that it's affecting accuracy then wouldn't you have bigger fish to fry than merely a case mouth that wasn't belled prior to seating?

I have seen some pretty ugly bullets shoot quite well , so long as the base of the bullet wasn't disturbed... Is this a scenario where the M die shines in that it allows the bullet to start seating without disrupting the jacket at the base?

 

[CatShooter]

How much of a difference does visual scratches on the jacket actually affect downrange performance?

I had approx. 60 bullets given back to me by a fellow shooter who bought a 100 count box of 139 lapua scenario OTM'S from me (same lot# as mine as I had bought 30 100 count boxes at once)

They were pulled using a forster collet puller and did show very slight signs such as scratches along the bearing surface.. I used those bullets at a later date and found them to go rite where the new ones printed (600 yds)

I guess what I'm saying is if your brass is stripping enough of the jacket off that it's affecting accuracy then wouldn't you have bigger fish to fry than merely a case mouth that wasn't belled prior to seating?

I have seen some pretty ugly bullets shoot quite well , so long as the base of the bullet wasn't disturbed... Is this a scenario where the M die shines in that it allows the bullet to start seating without disrupting the jacket at the base?

I have pulled match bullets from chamfered necks that were so badly gouged, they were only good for foulers.

Does it make a difference past a few hundred yards?? I don't know - but if we go trough all the efforts involved in case prep - then we go through the efforts of sorting and weighing bullets, then why knowingly shoot deformed bullets??

 

[kraky]

One positive I've seen floated on the chatrooms is that a slightly belled case mouth might help center the casing in the chamber a little better. Not sure it makes alot if difference but visually it could be a valid thought.

 

[Juma]

Annealed and Mdied cases seat so easily. Smooth as butter.