Tight PCC barrel

[alvinsmith75]

Good morning.   Looking for some direction on what I need to purchase.  I have many 9mm barrels at home and have been reloading for several years with over 40k 9mm reloads.  My reloads plunk test fine in all but 1 brand barrel.  It's a tight chamber issue and not a oal issue.  All of my rounds are within SAAMI spec.  I unfortunately have fixed this issue in the past with my dremel BUT would like to purchase the right tool for the job.  Is it a particular brand reamer I'm looking for?  Any help is appreciated, thanks.  

Oh and my oal is 1.085 because I build all my reloads for my CZ pistols.  

[George16]

Buy one of those Manson throating reamers. Or better yet, contact and send it to @MemphisMechanic. He reamed three of my czechmate barrels and I can now load up to 1.175” without any detrimental effects in accuracy. Turnaround was very quick and comms were very quick and professional.

[zzt]

Since you have a tight chamber problem, not a throating issue, buy a 'normal' reamer.  Both Clymer and Manson make excellent reamers.  When you bottom the reamer your throat (freebore) will be .055" or slightly more.  That will not harm accuracy with your short OAL.  If you want less freebore, call Manson and ask about their special reamers.

[alvinsmith75]

6 hours ago, zzt said:

Since you have a tight chamber problem, not a throating issue, buy a 'normal' reamer.  Both Clymer and Manson make excellent reamers.  When you bottom the reamer your throat (freebore) will be .055" or slightly more.  That will not harm accuracy with your short OAL.  If you want less freebore, call Manson and ask about their special reamers.

Got it figured out.  The case throat area is under spec.  This barrel was reamed with a worn out reamer evidently. I contacted Manson and said this measurement should be .381.  It's .379 and my rounds are crimped at .380.  I've ordered a new Manson reamer to clean it up.

[alvinsmith75]

8 hours ago, George16 said:

Buy one of those Manson throating reamers. Or better yet, contact and send it to @MemphisMechanic. He reamed three of my czechmate barrels and I can now load up to 1.175” without any detrimental effects in accuracy. Turnaround was very quick and comms were very quick and professional.

Thanks.  I've found the issue and ordered a new reamer.

[zzt]

3 minutes ago, alvinsmith75 said:

I've ordered a new Manson reamer to clean it up.

 

Nice.  The Manson reamer is super sharp.  Use a tap wrench or something like that and apply gentle pressure.  It cuts like butter, so DO NOT use a drill or other power tool.  Use lots of oil.  Since the reamer is new it will put knife edges on the lands.  So shoot a bunch jacketed, JHPs or heavy plate bullets through before you try any lead or coated.  If you don't the lands will cut the coating, leading the barrel.  It will also create a humongous smoke cloud.  Honestly, it will look like you shot a black powder round.

[George16]

46 minutes ago, alvinsmith75 said:

Thanks.  I've found the issue and ordered a new reamer.

Glad you got it all figured out.

[yigal]

5 hours ago, alvinsmith75 said:

Got it figured out.  The case throat area is under spec.  This barrel was reamed with a worn out reamer evidently. I contacted Manson and said this measurement should be .381.  It's .379 and my rounds are crimped at .380.  I've ordered a new Manson reamer to clean it up.

This is not the tool, which is suitable for accurately measuring internal diameter.

and i glad that now all o.k.