Large radius will leave sharp edges. A smaller radius will blend into the shaft of the pin (I Think).
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Large radius will leave sharp edges. A smaller radius will blend into the shaft of the pin (I Think).
I'll try and make a sketch.
Is this what you mean:
https://i.imgur.com/fI8GxqHl.jpg
So I made my firing pin look more like the photo on the right and it helped a lot with the cratering but didn't stop it entirely. I then made the firing pin a little more blunt but it failed to ignite the primers. I put it back more to what it is on the left and it fires okay but the cratering returned?
I also get really erratic velocities with this rifle (ES of 50 - 100fps is not uncommon). I've tried about everything I can think of but nothing works.
I then reviewed a diagram of the bolt assembly and noticed I had forgot to install a small ring between the firing pin spring and the bolt retainer spring. The spring has been missing for over a year but luckily I found it under my reloading bench and reinstalled it. I haven't had chance to shoot it since.
My question is: do you think the elimination of this little ring could be why my ES is so high?
On the radius of an ogive the larger the radius the pointier the tip.
https://www.tmtpages.com/draw/Helpfi...detail%201.png
I thought what you pictured is what I'm after. I'm sure a machinist/gunsmith could pull that off. Too bad I'm a carpenter! LOL!
Did you check the headspace after installing the new bolt head?
Did you check the firing pin protrusion after installing the new bolt head?
High ES/SD was not reported in any of your prior posts, this is new information.
Usually, but not exclusively, high ES may be due to inconsistent ignition. You say you've "tried everything". I'm not familiar at all with the 6 Remington...but, did you change primers? Powders? What's your % of case fill? I think more info on current load data, and what you've tried prior, would be relevant in seeking a solution.
All good posts here. When these options are tested and tried we often dig deeper to the less obvious problems.
One may be trigger function/settings. Another may be operation of the bolt/firing pin itself.
Is the trigger aftermarket? The overtravel screw even on a Savage factory screw set too tight can cause the sear to "rub" on the trigger giving variable primer strikes. Pin protrusion can be inconsistent possibly the cause of other issues like ES.
Same problems can happen with bolt/firing pin if dirty, rough, rusty, gunky or worn cocking pin problems exist.
Other "long shot" problems may be sear interfering with stock pillar.
Little things are often the hardest to spot. Just the trigger touching the trigger guard can cause issues.
My .02,
Randy
I don't believe any of the accutrigger models have an overtravel screw. A good check for sear interference with the trigger is to hold the trigger down and operate the bolt release through its full stroke. It should not "rub" the trigger behind the trigger sear. If it does something is preventing the trigger from moving back far enough. This is common where overtravel screws are used as in aftermarket triggers & the old three screw triggers.
Most of my Savage rifles crater primers even with lower charges or with factory ammo.. At first I was concerned too but started to pay close attention to the “normal” crater look to see if it started changing indicating pressures are increasing. As pressure increases the crater will start to look different. So far so good.
I had to hunt, but I found the picture.Attachment 6874
Yes, even on the 1-piece pin. As protrusion starts at .055”+. Gives a go on the 1-piece. But the OP, already having done this, most likely is about out of room. And he said it was having ignition problems. The adjustable pin has room to accomplish this reshaping many, many times over!
I shape my pins along these lines, but slightly different. I reduce the diameter via bevel, but only .035” of the pin(the protruded length so the pin is still fully supported in the bolt head.) Then I the make the pin face surface flat(as the posted picture).
I did measure the pin diameter at 0.0678"