Personally I would bump the shoulder more-- the most you could be sizing would be .003 and many of them wouldn't be getting any shoulder bump....
As far as the .004 difference- how accurate are you at measuring? If you measure the same piece of brass (without looking at the readout until you are done) 5 or 10 times do you get the exact same reading? I never did with the Hornady comparators....
The .004 difference is not causing bad groups--
Normally, I'd suspect me more than the Hornady Comparator, but I am pretty good with calipers, micrometers etc as I've got quite a bit of experience rebuilding engines.Originally Posted by Whynot
I just have questions about reloading and what happens to brass when you fire a gun. My Lapua brass measured anywhere from 1.529 to 1.531 when it was new. I swear it measured 1.536 to 1.538 after the first time it was fired. My Lee case trim gauge trims the brass to 1.912 so this brass has been shoulder bumped and trimmed to that length twice now.
On edit: I resized the new brass before I loaded it, but I didn't measure it after sizing so I don't know if it went straight from 1.529 to 1.5737 on firing or if it ended up somewhere in the middle after sizing. I used the standard setup with a FL sizing die which should have sized it to SAAMI specs.
It's been a little cool so I haven't been out to the range this week. I decided to see if I could measure the protrusion of the firing pin and this is what I found. From the end of the bolt to the top of the firing pin is .0475". I kept that measurement and zeroed the gauge and measured the distance to the bolt face. That measurement was .059". Then I closed the caliper, zeroed the gauge, and measured the distance from the end of the bolt to the bolt face. That measurement was .1065 which is close enough to confirm my first two measurements were essentially correct. I'm not sure how accurate my caliper is, but its close enough for this exercise. The protrusion is .059". Is that in spec?
Measurement to the top of the firing pin.
Measurement to the bolt face with after zeroing the gauge.
Measurement from the front of the bolt to the bolt face.
.059" will work, but better to have it ~35 thou. I think you could turn the pin cap 2 notches to get in that 25-35 thou range.
These are super cheap and great for measuring firing pins:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Great! Another tool I neeeed.
I don't think the firing pin protrusion is adjustable on the new savages.
Thanks for the pictures. Now You can see what Your true firing pin fall is, minus the explosion and blow back. With .059” firing pin protrusion, we would expect no less. Perhaps the Axis, new firing pin experts, can explain the solution to excessive fp protrusion on those platforms, or if it is in fact a problem.
IMO, at this point in time, You rifle, and platform, and loads, exceed expectations. Assuming that red dot on Your Target is 1”.
Congratulations
This is a touch off topic but for everyone taking in all of the information being tossed out on firing pin protrusion, I want to remind people that when you are setting up your firing pin, making measurements and al,l it is paramount that you consider the cocking piece and pin adjustment. This is a critical step in my opinion, when trying to troubleshoot light primer strikes and even accuracy issues. Setting the the correct length of travel starts at the cocking piece pin. That travel is impacted by the location of the firing pin stop and protrusion of the firing pin tip.---------------------------------------------------------------------------------------------------------------------------------------------- The reason many of us point out that .035" being the best place to be was initially what Fred Moreo from Sharp Shooter Supply guided us to understand. (Each position of the firing pin stop, 4 total per revolution, is equal to .009" Therefore everyone will find a protrusion between .035" and .044" with the older style firing pin assembly) Taking the wisdom that as delivered to us by not only a top Savage Gunsmith but also a benchrest shooter is something that should not be overlooked. I believe Freds knowledge and understanding of consistent firing pin impact to achieve consistent primer ignition was a part of his path to make Savage rifles shoot............................................. .................................................. ...........................................Back to firing pin protrusion and its affect on firing pin travel. Lets start at the difference between setting protrusion and the the actual protrusion when the trigger is pulled with a primered case/live round. Chad Dixon of long rifles messaged me a book of information on the topic. in that PM he informed me that a primer can be ignited with as little as .015" maybe less and at maximum the need was more likely to be around .025. Fred has posted something about this but I can't recall the exact numbers but I believe he stated he had spent the time to measure the depth of primer indentation for verification. Why is this important, for 98%(random number) it is not important. But if you have an ignition issue it may come in to play. ........................................So for the sake of conversation, if the firing pin travel is set at the approximate .250" from the shelf of the cocking ramp to .015" from bottoming out at the fired position, likely a little less after the Cocking Piece Pin is handed off to the sear, anything that reduces the length of protrusion affects the distance of the firing pin travel. Therefore if you set your protrusion at say .040" and your firing pin stops at .025" when the anvil is driven into the bottom of the primer pocket and the shoulder of the case is seated in the chamber, you have only lost .015 of travel length. (Shoulder bump is critical for proper clearance and primer ignition.)If your pin is set at .055" protrusion you loose maybe .030' of travel using those numbers. Now you are down to less than .200 travel possibly with manufacturing tolerances. .................................................. .................................................. .................................................. .................................................. .....These where slightly random thoughts from a older guy with some free time on his hands. I am very grateful to all of the knowledgeable guys that ultimately led me to these conclusions. Much of their dialog drove me to test and measure and inspect things. If you find something I have said to be discombobulated or untrue, I'm sorry. On the bright side I may have been the one to peak your interest enough to test my assertions. And for those of you who could care less...Chive on!
The Dunning-Kruger effect is alive and well.
thanks! The red circle is 1” and I’m happy with the progress so far. I think at this point, I’m looking for more consistent loads rather than more accuracy. I can make and shoot very small groups, but I still have outliers whether from an inconsistent load or lack of shooting accuracy on my part.
All you said sound good in my ear Robin
The new style firing pins aren’t adjustable, no. But you can still set protrusion if it’s too long. Measure for the appropriate amount it needs reduced. File to just shy of that amount. In your case, .059 less .035. So need reduced .024”. File .023” off flat. Put in a micro bevel for proper Radius & finish with sand paper. Round just the face but not past the bevel depth. A great way of getting it perfect is chucking in your drill press if you have one, or a hand drill held in a vice. Then use maybe 400grit sand paper in an arcing motion from bevel edge to bevel edge. Can finish the same action with 1000grit to remove any surface scratches & quick touch of Cold Blue. Sounds like many steps, but it’s not. It’s super easy. Things like this ya just go slow & measure often.
So, how necessary is this ? We see the accuracy achieved with the rifle in its present condition. Will this modification show vast improvement on target ? Is this modification more theoretical or actual ?All you said sound good in my ear Robin
The new style firing pins aren’t adjustable, no. But you can still set protrusion if it’s too long. Measure for the appropriate amount it needs reduced. File to just shy of that amount. In your case, .059 less .035. So need reduced .024”. File .023” off flat. Put in a micro bevel for proper Radius & finish with sand paper. Round just the face but not past the bevel depth. A great way of getting it perfect is chucking in your drill press if you have one, or a hand drill held in a vice. Then use maybe 400grit sand paper in an arcing motion from bevel edge to bevel edge. Can finish the same action with 1000grit to remove any surface scratches & quick touch of Cold Blue. Sounds like many steps, but it’s not. It’s super easy. Things like this ya just go slow & measure often.
I have a drill press and will probably give that a try after the first of the year. I have three weeks to shoot before we are leaving the country for a month-long trip and it'd drive me nuts to be right in the middle of that and have to leave.All you said sound good in my ear Robin
The new style firing pins aren’t adjustable, no. But you can still set protrusion if it’s too long. Measure for the appropriate amount it needs reduced. File to just shy of that amount. In your case, .059 less .035. So need reduced .024”. File .023” off flat. Put in a micro bevel for proper Radius & finish with sand paper. Round just the face but not past the bevel depth. A great way of getting it perfect is chucking in your drill press if you have one, or a hand drill held in a vice. Then use maybe 400grit sand paper in an arcing motion from bevel edge to bevel edge. Can finish the same action with 1000grit to remove any surface scratches & quick touch of Cold Blue. Sounds like many steps, but it’s not. It’s super easy. Things like this ya just go slow & measure often.
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