What's happening here? (hard bolt lift)

[rootacres]

Hard "bolt lift" or "bolt click" . . . not sure the correct term. Im referring to the top of the bolt lift being pretty tight.

I'm a little confused and need some people with more experience to possibly point me in the right direction.

7mm SAUM. ADG brass, pushing hammer hunters (143gr HH at 3070), Proof barrel w/ standard chamber, Bighorn Origin action.

So I'm not really pushing the load much in terms of speed or pressure. I shot my virgin ADG brass, no issues. Did my normal case prep, I use a Forster full length sizing die. I did the exact same load with the once fired brass. Nothing is tight upon chambering a round, after the shot the very top of the bolt lift is pretty tight.

This isn't my first short magnum, I'm not seeing pressure signs on the back of the case. Seems it may be the shoulder? What do I change to fix this?

Thanks

 

[lennywd87]

Any marking on the bolt lug faces where they mate to lock with the lugs of receiver?


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[ckrhtr]

A click at the top of the bolt can be an indication of pressure and it can also be an indication of incorrectly sized brass. I have several custom rifles that have minimum spec chambers, off the shelf dies do not size the lower portion of the case enough to allow for any expansion and I get clickers.
You should measure your before and after sizing and see if you have adequate sizing at the .200 line generally you should get a .002 reduction after sizing.

 

[rootacres]

A click at the top of the bolt can be an indication of pressure and it can also be an indication of incorrectly sized brass. I have several custom rifles that have minimum spec chambers, off the shelf dies do not size the lower portion of the case enough to allow for any expansion and I get clickers.
You should measure your before and after sizing and see if you have adequate sizing at the .200 line generally you should get a .002 reduction after sizing.

Im traveling for work so it'll be a few days before I can do this measurement. What dies do you use to size the bottom of your brass correctly?

 

[lennywd87]

Im traveling for work so it'll be a few days before I can do this measurement. What dies do you use to size the bottom of your brass correctly?

I use small base dies for this.


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[lennywd87]

@rootacres here is a good thread on the topic and might help your problem. They are talking about the 7saum in the Article as well. https://forum.accurateshooter.com/threads/small-base-die-options.4024756/

I usually bump my shoulders back .002 every resize on my ackley.


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[SDHNTR]

Small base dies for a bolt action? Interesting.

 

[MrSunday]

I have the same issue. 7 SAUM using ADG brass, Whidden Dies, and mild loads. I have diagnosed mine as a "Clicker". Here is an article on it.

Full-Length Sizing Die Fit — Diagnosing Stiff Bolt Lift Problems « Daily Bulletin

In this video, gunsmith Alex Wheeler explains how to ensure that your full-length sizing dies fit your brass properly. With many cartridge types, it's not unusual for factory dies to be slightly large in the bottom section.

bulletin.accurateshooter.com

Here is a video -Look for Clicker midway down on the right.

Videos | wheeleraccuracy

www.wheeleraccuracy.com

I called Whidden and explained the issue. The first thing they asked is if I am using ADG brass. They are familiar with the issue and offered to make me a custom FLS die. Sending my die and brass back today and hoping it fixes my problem.

 

[ckrhtr]

Im traveling for work so it'll be a few days before I can do this measurement. What dies do you use to size the bottom of your brass correctly?

I have purchased custom dies from Neil Jones and also Whidden to fix my problem.

 

[lennywd87]

Small base dies for a bolt action? Interesting.

@SDHNTR I’ve had to do it to form brass cycled through a .223 AR before in order to chamber them in a bolt action 700. Chamber dimensions don’t change because it’s a bolt action or semi auto. They sell small base dies for 22ppc, 6ppc, 6BR, 300wm. I don’t see many semi auto bench rest guns or semi auto 300wm. I guess us ND hunters just do thing different


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[Ucsdryder]

I’m not sure if it’s the same issue I had but at the top when the bolt lifted it would stick for a second. Almost like a click. Mine was a dirty chamber. Cleaned it really well with a 20ga mop and it went away.

 

[Ucsdryder]

Hard "bolt lift" or "bolt click" . . . not sure the correct term. Im referring to the top of the bolt lift being pretty tight.

I'm a little confused and need some people with more experience to possibly point me in the right direction.

7mm SAUM. ADG brass, pushing hammer hunters (143gr HH at 3070), Proof barrel w/ standard chamber, Bighorn Origin action.

So I'm not really pushing the load much in terms of speed or pressure. I shot my virgin ADG brass, no issues. Did my normal case prep, I use a Forster full length sizing die. I did the exact same load with the once fired brass. Nothing is tight upon chambering a round, after the shot the very top of the bolt lift is pretty tight.

This isn't my first short magnum, I'm not seeing pressure signs on the back of the case. Seems it may be the shoulder? What do I change to fix this?

Thanks

Did you fix the issue?

 

[rootacres]

Did you fix the issue?

Whidden gun works is testing my brass right now. They are going to see if their normal resizing die will work. If not Ill probably buy one of their custom dies. I guess this issue isnt too uncommon with ADG brass, especially in WSM/SAUM cases, in custom rifles. Hoping this solves my problem. Once I know for sure I will comment back on this post.

 

[wind gypsy]

I'm not sold on smaller based dies being a dependable solution for clicker issues.

In my limited experience I could measure a die resizing the web down a couple thousandths but it seems like once the web has expanded enough to cause a clicker, it is likely to expand too much again upon firing even if your sizing die squeezed it down.

 

[ckrhtr]

The issue that I have experienced is that the sizing die does not change the dimensions of the brass. New case at the .200 line measures .545 fired case measures .550 resized brass measures .550. This is particularly common in minimum spec custom chambers. I would agree that if you are getting adequate sizing at the .200 line then additional sizing may not benefit you.

 

[rootacres]

I'm not sold on smaller based dies being a dependable solution for clicker issues.

In my limited experience I could measure a die resizing the web down a couple thousandths but it seems like once the web has expanded enough to cause a clicker, it is likely to expand too much again upon firing even if your sizing die squeezed it down.

You could easily be right. Im not sure what the solution is. I have only reloaded for three rifles. All three have either been WSM or SAUM chambers. This is the first time I have ran into this particular issue. In my research it sounds like what I am experiencing isn't uncommon for ADG brass in 7 SAUM. So I figured I would go down that road and see what happens.

 

[wind gypsy]

You could easily be right. Im not sure what the solution is. I have only reloaded for three rifles. All three have either been WSM or SAUM chambers. This is the first time I have ran into this particular issue. In my research it sounds like what I am experiencing isn't uncommon for ADG brass in 7 SAUM. So I figured I would go down that road and see what happens.

Here's a long thread about clickers, primarily as it relates to the PRC chamberings. https://www.longrangehunting.com/threads/the-prc-die-problem.253223/

The other solution besides dies is making a little more room in your chamber which they discuss in the linked thread.

Edit to add, I've never had the issue in 300 WSM, 6.5 SAUM, or 7 SAUM with Norma or R-P brass. I have had mildly sticky bolt lift with ADG in 7 SAUM with warmish loads but not what i'd consider full on "clickers" like i dealt with in a 300 Norma. Seems like this issue is something ADG doesn't perform particularly well with across different cartridges.

 

[ckrhtr]

ADG brass is some of the hardest brass that I have ever used which is likely a contributing factor to the issue, but brass hardness is not necessarily the sole cause of the "Clicker" I have had the same thing with Nosler,WW, and Lapua. Measuring the brass new, fired and resized all showed the same thing, almost no reduction at the .200 after resizing fired brass.

The PRC issue is a case design issue which requires something other than custom dies.

 

[Cahunter805]

Whidden gun works is testing my brass right now. They are going to see if their normal resizing die will work. If not Ill probably buy one of their custom dies. I guess this issue isnt too uncommon with ADG brass, especially in WSM/SAUM cases, in custom rifles. Hoping this solves my problem. Once I know for sure I will comment back on this post.

This is a great choice and they make awesome dies. Curious what they find in their testing also.

 

[wind gypsy]

ADG brass is some of the hardest brass that I have ever used which is likely a contributing factor to the issue, but brass hardness is not necessarily the sole cause of the "Clicker" I have had the same thing with Nosler,WW, and Lapua. Measuring the brass new, fired and resized all showed the same thing, almost no reduction at the .200 after resizing fired brass.

The PRC issue is a case design issue which requires something other than custom dies.

Agreed. In this case i think it's a combination of chamber clearance AND how resistant a case is to expansion around 0.200" up from the case head. Hardness could be a factor but I think that's just one piece of the puzzle. If a case was even more prone to expansion at the web, more clearance in the chamber might not solve the issue.

In the 300 norma case where i experienced it, Lapua/Peterson cases just don't expand at the web like Norma brass cases did and thus are more resistant to clickers.