tammons
01-07-2013, 03:42 PM
I will start like this.
All the bolt lift I am talking about below is while cocking the firing pin.
I have an existing long flat back action with a lift ball bearing and works very smooth. Probably average lift.
This action was originally a 300 WM CF action.
New (to me) old long flat back action - stock. Very rough very hard lift and jumpy.
This is a bolt with the BAS that extends into the cocking piece sleeve.
This action was originally a 7mm RM push feed action.
Both bolts and firing pin assemblies are identical except the BAS.
After inspecting the rough lift bolt the cock pin ramp was very rough. Looks like it had been filed or just an extremely bad machine job.
Disassembled the bolt and ground and polished the ramp. Luckily that part worked out fine.
Polished all the other surfaces I thought needed it, cleaned, lubed etc.
Better but still a heavy bolt lift, but now smooth on the ramp.
At this point it is still probably about 1.5X what my other good bolt is with the lift kit.
While cocking the stiff bolt, Listening I hear the spring popping inside like it is binding.
My existing good bolt does not do this.
I tried swapping this and that to no avail, and finally swapped the firing pin assemblies and cocking piece sleeve.
Now my good bolt with the lift kit is stiffer (guessing most likely from the other firing pin assembly) and my new bolt that was originally very stiff and rough has a slightly less lift than the other.
Any help appreciated.
All the bolt lift I am talking about below is while cocking the firing pin.
I have an existing long flat back action with a lift ball bearing and works very smooth. Probably average lift.
This action was originally a 300 WM CF action.
New (to me) old long flat back action - stock. Very rough very hard lift and jumpy.
This is a bolt with the BAS that extends into the cocking piece sleeve.
This action was originally a 7mm RM push feed action.
Both bolts and firing pin assemblies are identical except the BAS.
After inspecting the rough lift bolt the cock pin ramp was very rough. Looks like it had been filed or just an extremely bad machine job.
Disassembled the bolt and ground and polished the ramp. Luckily that part worked out fine.
Polished all the other surfaces I thought needed it, cleaned, lubed etc.
Better but still a heavy bolt lift, but now smooth on the ramp.
At this point it is still probably about 1.5X what my other good bolt is with the lift kit.
While cocking the stiff bolt, Listening I hear the spring popping inside like it is binding.
My existing good bolt does not do this.
I tried swapping this and that to no avail, and finally swapped the firing pin assemblies and cocking piece sleeve.
Now my good bolt with the lift kit is stiffer (guessing most likely from the other firing pin assembly) and my new bolt that was originally very stiff and rough has a slightly less lift than the other.
Any help appreciated.