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ldpace
01-13-2016, 09:30 PM
I have just cut a new barrel for a 30 Br and when I chamber rounds some of them are difficult to chamber. Even empty brass, full length resized and Trimmed for proper length can be difficult. Some chamber fine, some have a stiff bolt closure but some require the bolt to be Pushed Forward and a definite "Click" can be heard before the bolt will close, you can feel the bolt move slightly forward before the bolt will close, but it is stiff. This is with the firing pin, extractor and ejector removed. Head space is fine, checked and double checked. The chamber looks fine, although I do not have a bore scope. Is there a fix or should I just move the chamber forward a thousandth and reset headspace? Thanks for any help.

CMaier
01-13-2016, 10:23 PM
Check your sizing/sizing die ??

Measure the sized cases

I have just cut a new barrel for a 30 Br and when I chamber rounds some of them are difficult to chamber. Even empty brass, full length resized and Trimmed for proper length can be difficult. Some chamber fine, some have a stiff bolt closure but some require the bolt to be Pushed Forward and a definite "Click" can be heard before the bolt will close, you can feel the bolt move slightly forward before the bolt will close, but it is stiff. This is with the firing pin, extractor and ejector removed. Head space is fine, checked and double checked. The chamber looks fine, although I do not have a bore scope. Is there a fix or should I just move the chamber forward a thousandth and reset headspace? Thanks for any help.

ldpace
01-13-2016, 10:38 PM
I am using the same Redding Competition FL neck Bushing Die that I have used for years on other barrels cut with this reamer and using the same action, a BAT 3L.

Dusty Stevens
01-13-2016, 11:01 PM
Carbon ring buildup in front of the case mouth?

Lucky Shooter A
01-13-2016, 11:05 PM
"some require the bolt to be Pushed Forward and a definite "Click" can be heard before the bolt will close, you can feel the bolt move slightly forward before the bolt will close,"

Does this suggest you might have difficulty getting the extractor to "click" over the case head ?

A. Weldy

Boyd Allen
01-14-2016, 01:59 AM
Have you checked the clearance between the nose of the bolt and the barrel's cone? Done any checking for contact with layout dye?

JerrySharrett
01-14-2016, 06:15 AM
Next question. Is this the same old brass but a new chamber?

,

ldpace
01-14-2016, 07:31 AM
Extractor has been removed from the Bolt.

Carbon Build up - I even re trimmed two case necks to make sure a doughnut had not formed.

Nose clearance is fine, with no shell the bolt just falls closed, even with head space gauge.

I have tried some fire formed brass and some that has not been fired in that chamber.

Yes this is the same old brass but all was fired in a chamber cut with the same reamer.

thanks for the replies

Jim Kobe
01-14-2016, 08:24 AM
Just because it was cut with the same reamer don't mean the chambers are the same!

ldpace
01-14-2016, 08:43 AM
That's why I am wondering if I need to just recut the chamber a thousandth forward and reset the tenon shoulder to reset headspace. I think I will try and re anneal the brass and see if I am getting spring back in case this is just a really tight chamber. I like a tight chamber:o

Greyfox
01-14-2016, 10:27 AM
That's why I am wondering if I need to just recut the chamber a thousandth forward and reset the tenon shoulder to reset headspace. I think I will try and re anneal the brass and see if I am getting spring back in case this is just a really tight chamber. I like a tight chamber:o

You might consider a different die. If you sent a couple of new, fireformed cases to Lynwood Harrell, you could get a die that would fit the chamber. The chamber is probably slightly different than the last one. Annealing will likely not make a difference as the issue is likely the base of the chamber rather than the shoulder. Of course, this is all speculation, but a die from Harrell's is an inexpensive fix.

Rick

ldpace
01-14-2016, 10:30 AM
I thought of that but a fire formed case will not rechamber. Would a body die from Redding do the same thing?

C.L. Peterson
01-14-2016, 10:41 AM
I have just cut a new barrel for a 30 Br and when I chamber rounds some of them are difficult to chamber. Even empty brass, full length resized and Trimmed for proper length can be difficult. Some chamber fine, some have a stiff bolt closure but some require the bolt to be Pushed Forward and a definite "Click" can be heard before the bolt will close, you can feel the bolt move slightly forward before the bolt will close, but it is stiff. This is with the firing pin, extractor and ejector removed. Head space is fine, checked and double checked. The chamber looks fine, although I do not have a bore scope. Is there a fix or should I just move the chamber forward a thousandth and reset headspace? Thanks for any help.

My thoughts

1.)Each new barrel needs its own new brass.
2.) Some even require a separate re sizing die to compliment the new chamber.
As stated earlier
Just because it was cut with the same reamer does not mean all chambers will be the same dimensions
different machinists, different steel properties, different lathe, different chambering techniques just to name a few variables

New brass may solve all your problems!
My 2 cents
CLP

coyotechet
01-14-2016, 10:57 AM
Sounds to me like you just cut a very nice close tolerances chamber. Just use new brass and you will be fine.
Chet

Dusty Stevens
01-14-2016, 12:10 PM
If the bolt just falls on a headspace gage dont cut it deeper.

CMaier
01-14-2016, 09:51 PM
Yes try new brass, new sizer.

If the bolt just falls on a headspace gage dont cut it deeper.

skeetlee
01-15-2016, 07:28 AM
brand new brass!!!!!!!

blades
01-15-2016, 09:56 AM
not to be a wise ass but was that reamer touched up any?

ldpace
01-15-2016, 11:40 AM
No the reamer is nearly new, this is the third chamber I have cut with it. All chambers were drilled and bored so the reamer did minimal work. I think a small base body type die or new brass will fix the problem. Hopefully it is not the chamber.

Wilbur
01-15-2016, 03:21 PM
Your initial post indicates that the problem is with the cases rather than the chamber. Cook up some new cases and let us know if that fixes the problem. You don't have to make more than five or so to determine if that fixes it.

ldpace
01-16-2016, 12:42 AM
I will do exactly that as soon as I can. Work gets in the way sometime.

rogn
01-20-2016, 10:45 PM
Could the rim be buggered or expanded on the old cases, enough to hang up on bolt closure. A batch of new cases should be an answere as was suggested.

ldpace
01-21-2016, 08:48 AM
Thanks for all the help. Finally worked it out. The brass was oversized by only 0.0005 just forward of the base/head. This was difficult for me to accurately measure. This area is supposed to be 0.471 on a 30 BR, I noticed that the .308 is supposed to be .470 at the same place, so I ran the cases through an Lee 308 FL sizing die with the decapping rod removed and it resized them enough to chamber without issue. My Redding Competition S FL neck bushing dies were not getting the FULL length resized. The previous chamber must have been slightly oversized in this area which created the problem. I have fire formed them and they rechamber fine even before resizing.

alinwa
01-22-2016, 01:45 PM
Thanks for all the help. Finally worked it out. The brass was oversized by only 0.0005 just forward of the base/head. This was difficult for me to accurately measure. This area is supposed to be 0.471 on a 30 BR, I noticed that the .308 is supposed to be .470 at the same place, so I ran the cases through an Lee 308 FL sizing die with the decapping rod removed and it resized them enough to chamber without issue. My Redding Competition S FL neck bushing dies were not getting the FULL length resized. The previous chamber must have been slightly oversized in this area which created the problem. I have fire formed them and they rechamber fine even before resizing.

Check post #15, coyotechet

;)

al

CMaier
01-22-2016, 04:53 PM
actually it appears post 2 was correct.


Check post #15, coyotechet

;)

al

F. Guffey
01-23-2016, 09:19 AM
Sounds to me like you just cut a very nice close tolerances chamber. Just use new brass and you will be fine.
Chet

Or he needs help sizing cases to fit his chamber.

F. Guffey

F. Guffey
01-23-2016, 09:20 AM
Head space is fine, checked and double checked. The chamber looks fine, although I do not have a bore scope. Is there a fix or should I just move the chamber forward a thousandth and reset headspace? Thanks for any help.

You hit a wall; I like the part about ‘the double check’. I am unorthodox when it comes to measuring chambers. , I measure short chambers and I measure long chambers. I would not start on a chamber until I determined how far the reamer had to be advanced to complete (the chamber). Then there are head space gages. When making head space gages I never understood the infatuation with one head space gage. I like the idea of knowing how far I have to go, then there is that part about going too far, I want to know ‘by how far’.

Then there is the completed chamber with the bolt installed; the bolt makes the chamber a dark place and most difficult to see anything; that should not be a problem. All of my dies and presses have threads; threads allow me to adjust the die to, off or below the top of the shell holder. Most reloaders are fire formers; they chamber a round then pull the trigger and then become fire formers. I form first then fire.

Forming before firing is difficult if for no other reason there is a shortage of brass for reloaders that know what they are doing. I have long chamber; my long chambers are long from the shoulder to the bolt face. One chamber is .016” longer than a minimum length/full length sized case. To put it another way the chamber is .011” longer than a go-gage length chamber or .002” longer than a field reject length gage when the cage is measured from the shoulder to the head of the cage.

When forming cases for the long chamber I use 280 Remington cases. I adjust the die off the shell holder .014” then form the case and finish by full length sizing with the .014” gap between the shell holder and bottom of the die. The .014” give me the magic .002” clearance. Bump? More like wrecked it; I shortened the 280 case from the shoulder to the head of the case .037” and no the shoulder did not move.

My cases do not have head space because SAAMI does not designate head space for the case, the symbol for head space is absent on the case drawing. This does not lock me up or drive me to the curb. I use the length of the case from the shoulder to the case head to off set head space in the chamber from the shoulder of the chamber to the bolt face.

Chamber cast; that is another topic that has never been finished when discussed on a reloading forum.

F. Guffey