Bolt Click?
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supercrossbmx69
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That bolt "click" more then likely means your loads are way over pressure and you need to back off your load.
Full-Length Bushing Dies and Die Conversions
Read this article but in a nutshell, you have two different metals (brass case and steel chamber) expanding and contracting differently. One comes back to original dimension (chamber) and the brass does not.
The click can come from over pressure loads fired once OR brass that has been fired multiple times and not FL sized correctly or at all.
Brass when fired will expand and at the same time the steel chamber expands. The brass does not return to its original dimension while the steel chamber does. IF you are NS only and firing at close to SAAMI PSI in particular, the brass is going to continue to expand each time you fire it, primarily at the base. This causes the brass to bind eventually unless you are loading well below SAAMI. You can fire a case way over pressure and get the same binding. That is a sure sign of excess pressure for load development.
The key is a set of dies that MATCH your chamber and give you the .001 squeeze at the base of the die to control the brass and FL size every time or use a fitted body die to size the case bottom. JLC dies do that and they do not use expander balls to pull on the necks. Dave Kiff at PTG makes the reamers for Redding dies, so he can provide a reamer that will work with Redding dies.
I use a lot of JLC conversion dies to match factory chambers and custom Neil Jones dies that are perfectly matched to my chamber. I just sent a reamer print to John Widden to confirm his die sets will match my chamber for a new 6 Dasher.
Read this article but in a nutshell, you have two different metals (brass case and steel chamber) expanding and contracting differently. One comes back to original dimension (chamber) and the brass does not.
The click can come from over pressure loads fired once OR brass that has been fired multiple times and not FL sized correctly or at all.
Brass when fired will expand and at the same time the steel chamber expands. The brass does not return to its original dimension while the steel chamber does. IF you are NS only and firing at close to SAAMI PSI in particular, the brass is going to continue to expand each time you fire it, primarily at the base. This causes the brass to bind eventually unless you are loading well below SAAMI. You can fire a case way over pressure and get the same binding. That is a sure sign of excess pressure for load development.
The key is a set of dies that MATCH your chamber and give you the .001 squeeze at the base of the die to control the brass and FL size every time or use a fitted body die to size the case bottom. JLC dies do that and they do not use expander balls to pull on the necks. Dave Kiff at PTG makes the reamers for Redding dies, so he can provide a reamer that will work with Redding dies.
I use a lot of JLC conversion dies to match factory chambers and custom Neil Jones dies that are perfectly matched to my chamber. I just sent a reamer print to John Widden to confirm his die sets will match my chamber for a new 6 Dasher.
Bigeclipse
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I do not mean to hijack this thread but I am relatively new to reloading and just started some neck sizing only on my 7mm rem mag. I am at the book value high load but my velocity is almost 100fps below the book value so I may be still under SAAMI pressures. Never heard of this "bolt click" thing until I read this thread. I have not noticed anything with my loads "yet". Is this click a sound when shooting, extracting the brass from chamber...some other time? How loud is the click and do you think I should be worried.
The condition I had was a hand load 42.5 of varget loaded .02 jump of a berger .308 175 hunting vld. Bolt would come up easy then sort of need a little pop at the top, not real hard but I noticed it. This has been a pet load for a long time so it sort of surprised me. 2650 is average over chronograph. Im suspect I may have used a different primer wlrm instead of wlr. That being the only difference. Thanks for the help folks
The click is right at the top of the bolt cycle while opening to unchamber a round. It is the last 1/16" to 1/8" of movement and may not make a click noise, but has a click feel to the movement. It normally takes a little pressure to open the last little bit and reminds me of a trigger that is set very stiff. Pull, pull pull, then click. Hope that helps.
Reuben
Reuben
dkhunt14
Well-Known Member
Yep that is what it is like. Probably not a good thing to have when hunting animals that can eat you. Matt
The click you experince is not unusual. It is commonly caused by the base of your brass being too wide for the chamber. You can try bringing your F/L die down as far as possible, but you may push the shoulder back too far. A Redding body die will solve the problem if you follow the set up instructions.
I have encountered this snick of bolt opening resistance with the thicker case of a 7mm/375 Ruger wildcat I made last year. Virgin brass worked fine but once fired or more had that snick regardless of powder charge. A fellow poster shared a inexpensive method that has worked.
A FL die has its upper section machined off so there is no shoulder and neck. Some of lower portion of the die is also machined. This leaves a tapered tube. (it is hell on a Carbide tool bit and makes some interesting orange sparks till it cuts through the case hardening) The body sizer can be adjusted so it will reduce the taper in the lower portion of the cartridge.
There is one small issue in this approach. The cartridge becomes longer requiring shoulder sizing. No big deal just one more step. It solved my issue and has made the multiple fired cases useful again.
A FL die has its upper section machined off so there is no shoulder and neck. Some of lower portion of the die is also machined. This leaves a tapered tube. (it is hell on a Carbide tool bit and makes some interesting orange sparks till it cuts through the case hardening) The body sizer can be adjusted so it will reduce the taper in the lower portion of the cartridge.
There is one small issue in this approach. The cartridge becomes longer requiring shoulder sizing. No big deal just one more step. It solved my issue and has made the multiple fired cases useful again.
