Neck shoulder junction question

[SRM]

Put together a 22 Dasher and missed this little area. Kinda figured that industry had some standards but....

The reamer was to my specs but I missed the radius in the corner and it came with no radius and I went ahead and cut the chamber , assembled rifle , bedded and all.

Fire formed some round with false shoulder, .005" crush and .005" jam on bullet. Blew out nicely!! Well, the neck shoulder is sharp and I'm a little concerned about neck separation . Should I polish my chamber there a little ? Kind of want to send the reamer back for Regrind as my throat is short anyhow but I do have a throater. Throater is .002" over bullet dia which I don't like.

Do y'alls dashers have radius there or should I just shoot this thing?

 

[ASbobcat]

Put together a 22 Dasher and missed this little area. Kinda figured that industry had some standards but....

The reamer was to my specs but I missed the radius in the corner and it came with no radius and I went ahead and cut the chamber , assembled rifle , bedded and all.

Fire formed some round with false shoulder, .005" crush and .005" jam on bullet. Blew out nicely!! Well, the neck shoulder is sharp and I'm a little concerned about neck separation . Should I polish my chamber there a little ? Kind of want to send the reamer back for Regrind as my throat is short anyhow but I do have a throater. Throater is .002" over bullet dia which I don't like.

Do y'alls dashers have radius there or should I just shoot this thing?

I think your concern may be warranted. Not sure that polishing will adequately fix the problem. Since you have a throating reamer, I think that's a good solution, especially since your throat is shorter than you like.Seems like a win-win situation.
It has been demonstrated and documented on this site that "tight necks" are generally overrated. They have a questionable accuracy advantage and many downsides, including possible turning necessity and clearance issues as necks thicken from flow. Many barrel manufacturers are now going with .003-.005 over loaded diameter with no reported effect on accuracy.
I have owned several calibers that were only .001-.002 over and eventually ran into clearance issues with all of them.

 

[ab_bentley]

Put together a 22 Dasher and missed this little area. Kinda figured that industry had some standards but....

The reamer was to my specs but I missed the radius in the corner and it came with no radius and I went ahead and cut the chamber , assembled rifle , bedded and all.

Fire formed some round with false shoulder, .005" crush and .005" jam on bullet. Blew out nicely!! Well, the neck shoulder is sharp and I'm a little concerned about neck separation . Should I polish my chamber there a little ? Kind of want to send the reamer back for Regrind as my throat is short anyhow but I do have a throater. Throater is .002" over bullet dia which I don't like.

Do y'alls dashers have radius there or should I just shoot this thing?

Have you had a neck separation prior? In any case?

Adam

 

[asauer]

I think your concern may be warranted. Not sure that polishing will adequately fix the problem. Since you have a throating reamer, I think that's a good solution, especially since your throat is shorter than you like.Seems like a win-win situation.
It has been demonstrated and documented on this site that "tight necks" are generally overrated. They have a questionable accuracy advantage and many downsides, including possible turning necessity and clearance issues as necks thicken from flow. Many barrel manufacturers are now going with .003-.005 over loaded diameter with no reported effect on accuracy.
I have owned several calibers that were only .001-.002 over and eventually ran into clearance issues with all of them.

He's talking about the throater (hence, the throat in the rifle), not the neck area. I wouldn't like having .002" over bullet diameter in the throat on a precision gun, but that's just me. I have been doing .0005-.001" over. It will probably still shoot well, but maybe you could just set the gun aside and wait on a regrind?

 

[ASbobcat]

He's talking about the throater (hence, the throat in the rifle), not the neck area. I wouldn't like having .002" over bullet diameter in the throat on a precision gun, but that's just me. I have been doing .0005-.001" over. It will probably still shoot well, but maybe you could just set the gun aside and wait on a regrind?

You are right, my mistake.

 

[SRM]

Have you had a neck separation prior? In any case?

Adam

Never have I had this happen. Only time I saw was and old Federal nickel plated 6x45 that was neck turned.

Never see the sharp n/s junction either.

 

[SRM]

He's talking about the throater (hence, the throat in the rifle), not the neck area. I wouldn't like having .002" over bullet diameter in the throat on a precision gun, but that's just me. I have been doing .0005-.001" over. It will probably still shoot well, but maybe you could just set the gun aside and wait on a regrind?

Thanks for info. Not sure why this throater is oversize. Seen them on Brownells and same .002 over.

 

[gunsandgunsmithing]

I've cut chambers using a reamer of a smaller caliber but same cartridge, ie, a 30-284, by chambering with a 6.5-284 reamer followed by a chucking reamer to form the neck and a throated to form the throat. Obviously, this method leaves a sharp neck/shoulder junction. It works fine. I've also used a chucking reamer to open the neck on chambers that were smaller than wanted. An example of this is a 220 Beggs that had a .243 neck that I opened to .250. I tied a record with that barrel and the brass lasted a long time. In fact, I'm still shooting the same brass in the third barrel. I've never personally had a neck come off. I have seen a few come off and feel that it's a neck turning issue.

 

[SRM]

Did you have any issues resizing?

 

[gunsandgunsmithing]

Did you have any issues resizing?

No. I typically use bushing dies and they never touch a small area at the neck shoulder junction. I doubt that has any bearing on the subject, as that's what most people use in br but that is a thought...I suppose a standard type die could cut the brass in that area if a sharp edge is left inside of the die but I've never seen or heard of it happening. I make some custom bushing dies where opening the shelf that holds the bushing leaves a sharp edge near the neck shoulder junction until I polish and de-burr it. The burr is a few thou below the neck and will leave a mark on the brass if left. I suppose if it were actually at the junction, and the burr left, that after repeated sizing, it could very well cause necks to break off.

 

[SRM]

Thanks for all the replies. Will report back.