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bigbird34
October 22, 2007, 09:18 PM
Hello Folks,I was given a Mauser 98(8x57mm) by a friend of mine several years ago....it was sportized a bit (basically a hand made stock),but we did a better job,new safety,new trigger and a new(well new to us) stock off of ebay ,I had a local smith do all the work....anyhow ,my oldest son has decided he needs to site it in for deer hunting (2 weeks) away (no pressure) the gun is missfiring quite a bit,the primers are not being struck hard enough ....soooooo I downloaded disassembly instructions from the web and took the bolt apart figuring it was dirty or something,well upon disassembly I can't really find anything wrong ,I polished up a few pieces on the firing pin,but no debris or crud???? I did measure the firing pin when decocked and it's right around .050" to .055" ...is this adaquate length or has the firing pin worn down from age ?????? I was told the military primers were very hard and would wear out the firing pin.....
I need to get my friend 8x57 dies and I'm gonna load up some blanks and see what happens ,but any ideas insights from you folks would sure be appreciated .....TIA BB34

James K
October 22, 2007, 09:38 PM
First, what ammo are you using? Some of the old milsurp ammo is not only corrosive primed but given to misfires. (To some folks, a dead primer strike looks like a weak strike because the primer metal doesn't flow back around the firing pin as it does when the round fires.)

If the ammo is OK (best way to tell is to fire it in another rifle), then check the firing pin spring. Sometimes folks cut them down to make it easier to cock the rifle. A firing pin protrusion of .055" should be OK, though I like to see them a bit longer, say .060".

FWIW, I have never heard of a Mauser firing pin wearing down with age; they are sometimes chipped by improper disassembly and then polished down to round off the tip, but worn down? I don't think so.

Jim

bigbird34
October 23, 2007, 06:17 AM
Thank you for the reply,I am using reloaded ammo,that I did myself ....It"s most probably a firing pin issue,but I'll know more today when a just reprime some shells and give her a test ......primers are cheaper to shoot ,than running to the range 45 min.away for another test .....if 6 primed shells fire,then up to the range we go,if not a new firing pin will be ordered....the spring looks original ,and is full of tension,but I may replace it also ....Thanks again ,BB34

bigbird34
October 23, 2007, 05:36 PM
Ok,The bolt is back together and in the gun,I resized and primed up 12 shells,and all fired :D,Sooooooooo,I told eldest son to head to the range this weekend and give her another try,I'm going hunting and don't have the time to test the mauser .....My old buddy said the reloading dies might be setting the shoulder back to far creating more head space ???? but the shell is tapered ,so I can't see how this would affect the placement of the shell in the bore ??? Unless by pushing the shoulder back to much I actually shrink the diameter of the shell enough ,so that it does go in the bore to far ....I have adjusted the RCBS dies as instructed by the manual,maybe I need to back the die off one revolution and give that a try ???? ....Asssuming I don't full size far enough down the case length ,the bolt should close harder ,"correct"???
TIA for any and all comments,BB34

VaFisher
October 23, 2007, 06:37 PM
I just had the same problem with a swede M-96 that had a sportized stock. Come to fine out the bolt was touching the stock enough to keep it from the normal 90 deg so the firing pin was not coming out enough as a result made it only barely hit the primer. Cut the stock out a bit and it works fine now so it may be worth looking at on your 98.

Harry Bonar
October 23, 2007, 07:43 PM
Sir:
never, never GO BY THE DIRECTIONS WITH THE DIES!! aLSO, YOU ABSOLUTELY NEED YOUR RIFLE CHECKED FOR HEADSPACE.
98S. - THE GERMANS DIDN'T WORRY TOO MUCH ABOUT HEADSPACE BECAUSE THE ROUND WOULD GET DIRTY IN COMBAT!
If you're using military ammo, that is probably the problem (if you have a missfire wait 30 seconds before you open the bolt!!)
Generally, if your serial numbers match the rifle will have correct headspace (safe within limits).

Do not follow the die makers directions.
Screw the sizing die town until with the ram at TDC, it just touches and then back off 1/2 turn. - Size a case - try it in your rifle - if it closes you have a problem - if it doesn't proceed and keep screwing the sizer down minutely till case will close with some feel on bolt handle as it closes - LEAVE IT THERE!
Be sure your striker mechanism is screwed in until it stops and locks!
DO NOT, repeat DO NOT fire anyones reloads! NO ONES! .050 pin protrusion is OK.
It is very unusual for a 98 to exibit this problem! It needs expert investigation. Hope this helps you.
If you follow the die makers instructions you will have incipient case head separation after about 3 to 5 reloads - you will be oversizing your case.
I very seriously doubt there is much wrong with your rifle unless something seriously wrong such as massive set-back - Germans allowed tolerance in the 98s - but as I said, if you find one with matching numbers (bolt and action) it'll be ok!
Harry B.

44 AMP
October 23, 2007, 08:57 PM
Is always a good idea with old rifles. However, I don't see how excessive (case too small) headspace would give misfires, as the Mauser extractor holds the case head against the bolt, and should hold it in place well enough to fire, even is the case is undersized. Firing a grossly undersized case is a bad thing, but a Mauser 98 can let you do it.

All the other ideas are plausible, and should be checked. If the bolt is fully shut, the pin long enough, the spring strong enough, then something is dragging on the striker, slowing it down. Or you have some bad ammo.

Have the gun checked over by a professional.

James K
October 23, 2007, 09:22 PM
If the case is not supported on the shoulder as it should be, but is held only by the extractor, the firing pin can push the case forward to the extent allowed by the extractor. This can absorb firing pin energy that is needed to fire the primer or, if firing pin protrusion is on the short side, can actually push the case forward to the extent of the firing pin protrusion without enough left to dent the primer.

Either way, yes a short case or excess headspace can cause misfires.

Jim

smiljko
October 25, 2007, 03:47 AM
Missfire
I just had the same problem with a swede M-96 that had a sportized stock. Come to fine out the bolt was touching the stock enough to keep it from the normal 90 deg so the firing pin was not coming out enough as a result made it only barely hit the primer. Cut the stock out a bit and it works fine now so it may be worth looking at on your 98.

I have seen this happen-and you said that you changed the stock. I would check if that is the problem.

Cheers

James K
October 25, 2007, 06:40 PM
All bolt rifles are designed so they won't fire unless the bolt is fully closed and locked. Anything (stock, dirt) that prevents the bolt from locking down fully will let the cocking piece drop onto the side of the cocking cam and not reach the primer.

It is something to check if the bolt has been bent down, new handle welded on, or stock work has been done, but is usually pretty obvious.

Jim

PzGren
October 26, 2007, 04:29 AM
THE GERMANS DIDN'T WORRY TOO MUCH ABOUT HEADSPACE BECAUSE THE ROUND WOULD GET DIRTY IN COMBAT!


That's interesting! The German guns have Waffenamtabnahmestempel and the guys that checked the guns were very anal about even the smallest piece. All guns proofed in Germany had to be proof fired and the chamber checked.

44 AMP
October 26, 2007, 09:03 PM
Decided you are entirely correct, and I was not taking into account the distance the case might move forward before being stopped by the extractor. I am now of the opinion that an undersize case may fire, or may not, depending on the amount of movement before being stopped by the extractor.

I neglected to take into account that even a tiny bit of play could cushion the firning pin blow enough to allow misfires. I should have remembered better, as this was something I once knew. Thanks for pointing it out sir.

My bad. :o

James K
October 27, 2007, 12:47 AM
Just for info. In spite of the German insistence on numbering everything, the Mauser production machinery was pretty good. A friend and I once had at hand 13 or 14 Mauser 98 rifles, from six different countries. We also had a set of headspace gauges and some time. So we started swapping bolts. I don't know how many different combinations we tried before we got tired, but none we tried (or were able to try) failed the field gauge and just about all were OK with both the Go and No-Go.

I thought that was pretty impressive and quit worrying overly much about Mausers being "in spec."

Jim

PzGren
October 27, 2007, 05:41 AM
Most machinery to produce K98 Mauser rifles had come from Germany as reparations after WWI, FN received the Mauser Werke machines and Czechoslovakia got Loewe's equipment and over 100,000 actions.

Harry Bonar
October 27, 2007, 01:37 PM
Sirs:
Yes, I agree their machinery was good - yes, I agree that swapped bolts from guns made all over the world will work, yes I agree that they all probably are safe, but I have found some Mausers with headspace that were far, far from my standards for correct headspace. Even A-Square recommends to turn the bbl. back a few thousandths before sporterizing the 98. and guaging it. To my standards I want the bolt to just wiggle down with the go guage!
I agree with you all that virtually all Mausers will fire with any 8X57JS ammo safely but I'm talking about correct headspace and the facts I've learned of 50 years of fooling with them.
Mausers with "set-back" cannot have the correct headspace! I've found dozens with set-back! Will they fire and not blow-up, certainly!
I had a Sako AII in 22-50, very accurate - it would also almost close on the no-go guage - not satisfactory for my taste - but maybe I'm just an old coger too hard to please.:) Headspace in a rifle isn't a matter of "will it shoot and not blow-up, it's a matter of being right!
Harry B.

Harry Bonar
October 27, 2007, 01:57 PM
Sirs:
8X57JS loaded in this country is at probably 35,000 CUP. while Turkish and German ammo is loaded to close to 50,000 CUP.

I cannot stress to strongly that headspace must be correct as it is (can be) a matter of life and death! Yes, most rifles will fire a round that has atrocious headspace but that's just one round, and some rounds are steel cases!
It is a known fact that military weapons headspace practice is to allow dirty ammo to load and fire - I wouldn,t want a tightly chambered and headspaced weapon in conbat - suicide!
We must realize that "handloading" practice in our society is pretty sloppy - little thought is given to the finer points. If we will buy one manual (A-Square Shooters Manual - Any Shot You Want) we wouldn't be so uneducated - yea! I was uneducated and I did some stupid things before I got educated but it's no excuse. We shouldn't be satisfied with "what will work" but only with, "what's right." And I don't mean any offense to anyone on the Forum at all - I just feel strongly about this!
Harry B.:D

Harry Bonar
October 27, 2007, 02:14 PM
Sirs:
In PrezGrens, post my statement in my initial post supports Jims' statement, not cobtradicts it, I said, if your numbers match it's probably within safe limits and that's what Jim's saying and I agree with him basically.
Here on the Forum we're interested in giving good info, not to pic each others posts to pieces. I don't think any of us are on much of an ego trip but it bothers me to see anyones post misrepresented.
Jim and I agree on Mausers - yea they're all pretty safe, but we're not interested in that - we're interested in giving you the best info. I'm sorry this has affected me so but I guess I'm just thin skinned about some things.
I apologize Harry B.:D

Jimro
October 27, 2007, 03:30 PM
Good advice has already been given about the bolt not being able to set in at the proper 90 degrees, the stock is usually the culprit but if the bolt was bent for a scope then the receiver needs to be notched, and if the notch isn't cut properly it too can prevent the bolt from setting properly.

Also weak springs are common on old Mausers, a Wolff spring is a cheap and worthwhile upgrade.

Also your reloads might be the culprit, you could possibly be seating the primers too deep or you have a bad batch of primers. I know I've had some bad primers before.

All told I hope this helps.

Jimro

PzGren
October 28, 2007, 04:24 AM
In PrezGrens...

Harry,

It is PzGren, chosen after the unit I served in, the 173. Panzergrenadierbatallion. I have read the technical manuals in the Bundeswehr and, having lived in Germany almost half my life, can assure you that there was and still is no slack when it comes to proper weapons maintenance.

As time went by, and a lot of time passed since the Mausers had been checked, the headspace could change.

When I still lived in Germany I wanted to buy a Swedish M38 and the dealer told me to wait a while because all the imports had to be proof fired and the ones that had passed had been sold. The ones that did not pass had the barrel set back and the chamber recut to proper specs before they were proofed and up for sale. A qualified gun smith performed the work. To work as an independent gun smith the three year associate degree is not sufficient, a Master's degree is required. I am mentioning this to show how much attention to detail and doing things right is given in Germany.

..and it's all written down in a regulation and followed, if necessarily at the cost of life:D

Harry Bonar
October 28, 2007, 08:00 AM
Sir:
I understand.
Harry B.

bigbird34
October 29, 2007, 08:36 AM
Hello Folks, I was able to test and site-in the 8x57 Mauser this past weekend,my son asked me to take it to our hunting location and test it out ...the bolt was cleaned inside and out and inspected by ME,(I cleaned up the firing pin well)the ammo were reloads ,done by ME,The stock was a used Mauser stock won on ebay ,that fit the action,the trigger safety and barrel bedding was done by a professional gunsmith ......so.....six shots fired ,all went off! Sited in for 100 yards ,around a 3.5" group,now when time is available,I'll hone it in .....
I have learned something new ,how to take apart a Mauser bolt ,clean it,inspect it ,and try it,and see what happens ......I am not fearfull of my mechanical abilities ,and if there were any doubts in my mind it would have gone back up to a pro,to be repaired/resolved .....Thank-you all for your post ,it's good to know that there are others who care about the safety and well being of an avid hunter/shooter ,Thanks again.....Bigbird34 a.k.a. Jim:D

PzGren
October 29, 2007, 02:29 PM
Jim,
You are on your way!!! Here is some info you might enjoy

http://parallaxscurioandrelicfirearmsforums.yuku.com/forums/81/t/German-Military-Mausers-Forum.html

jrfoxx
November 4, 2007, 03:35 AM
Also weak springs are common on old Mausers, a Wolff spring is a cheap and worthwhile upgrade.

Agreed this is defintely a possibility.Also, its a very cheap and easy fix.If it works, you fixed it for about $15, if not, you eliminated 1 possibilty, and it only cost you $15, and now you have a backup spring if you need one in the future.I had the same issue with a Turk Mauser model 1893. I Put the heavy Wolff spring in it, and it's 100% reliable now.Just my .02 cents....

PzGren
November 4, 2007, 05:48 AM
Before I'd rush to buy a new spring, I would first measure it's length and see if it is within spec.

Harry Bonar
November 4, 2007, 09:06 AM
Sir:
Thank you for your very informative posts!
Do you have any information on Mauser metallurgy, heat treat (carburizing), how it was done, oven, induction just in the ring, etc.
I'd simply love to have some info.
I've used Turk 38s. to build 416 Taylor, 9.3X64, 9.3X62, and U.S. calibers. I've, of course, used the VZ24s as well.
The Turks, roundly relegated to "rifles to be hauled around in the back of your pick-up" are fine rifles.
After truing the action face, removing the forend flange (leaves the action standard length as a VZ24) and generally truing things up makes as nice a rifle as a fine VZ24!
On drilling for mounts the O.D. drills fine but as you get into the interior it's so hard the drill will "sing" on the interior carburized interior! Looks like a fine heat treat to me. Yes, some of the bbls. I could have unscrewed by hand and a few crazy crests on the ring, but all have made fine rifles exhibiting NO set-back on any of them!
If I could have just been a little mouse in some Mauser plants!!
The paucity of information (technical) is madnening! Do you have more information, if so I'd be in your debt if you would be so inclined to share it. Thank you, and "May you live in interesting times."
Harry B.

Varmitzapper
November 7, 2007, 07:28 PM
Try visiting Mauser Central.com
Post your question there. Those guys live and breath Mausers.
Best i've seen on the net.

4V50 Gary
November 10, 2007, 10:12 PM
Thorough cleaning and good ammunition was all that was required?

Sometimes that's not at all surprising. About 90% of all gun malfunctions may be attributed to the weapon being dirty or poorly maintained. Then again there's bad ammo too.

bigbird34
November 11, 2007, 07:37 PM
Well, I brought my son up to the range last weekend (friday) to show him his gun was fixed.....unfortunatley, after several rounds the gun misfired again,again,and again.....:mad:
So I thought it might be bad primers,I could not remember what vintage the primers were ......:rolleyes:
So today I loaded up 20 more rounds,paying close attention to everything,case prep,primers used,shoulder length and overall length ....all 20 are good to go...:D
I setup my target at 100 yards,the 8mm is sighted in,I feel confident....number one thru number six fire without a hitch ....number seven does not fire :eek:what the hell,primer is indented but ,I didn't get the "click" I was expecting ,I rechambered the shell and it fired ???? The next five shells fired also ,for a total of 12 firing I had one missfire ,NOT GOOD ODDS !
Well I think I need a new firing pin and spring ,but I don't really know what the standard lenght of the firing pin should be,so I looked up one on Gunbroker.com,the seller states 7-1/4" long ,my F.P. is a tad longer (7-3/8"o.a.l.) so I assume my firing pin is good ??? Then I started looking at springs,a surplus spring measured 5-1/4 inches,(mine is 5 inches ??? my spring that is :)anyhow if you got to Midwayusa.com they sell 3 different springs,a 24,26 and 30 pound spring ??? which one should I purchase ??? 26 pound seems like average,but I'm not sure what one to get .
Anyhow any and all advice will be weighed ,before I make a purchase ....my son used my 338-06 this past weekend so there is no rush to get the mauser repaired....I just want to get it ready for next fall,and I want to be 100% confident that it will work correctly for my son......TIA Bigbird34

Harry Bonar
November 12, 2007, 05:56 PM
Naw!
I smell an amunition problem or a handloading problem! Any Mauser that's properly chambered has never misfired except with old ammo!
I've had old corrosive stuff that would go "click------------boom" quite a while later, but never one with factory or good lillitary ammo!
Something's fishy here. Even one with everything wrong (which is exceedingly rare) will hold the shell by the extractor enough to fire!:confused:
Harry B.:confused:

PzGren
November 13, 2007, 06:20 AM
what the hell,primer is indented but ,I didn't get the "click" I was expecting ,I rechambered the shell and it fired ????

That is generally the sign for a primer not seated deep enough and for hard primers.
Somehow I suspect the primer seating to be responsible for your problems, to eliminate all possibilities, ream your primer pockets and make sure that the primer is seated deeper than the case head - unless you already do that.

bigbird34
November 13, 2007, 07:30 AM
PZgren,the primer pockets were all cleaned by "me" primers were installed using a RCBS hand priming tool .....I'm not new at this, I have primed thousands of pieces of brass....all the primers looked alike when completed .....

I am leaning towards buying the 26 pound spring ,what is your opinion on my choice ?

TIA Bigbird34

PzGren
November 13, 2007, 02:54 PM
Bigbird,

the 26 lbs spring sounds like a good way to eliminate the next possibility.

This is just a wild guess but how is the exractor tension when you take the bolt out and keep a cartridge under the extractor?

James K
November 13, 2007, 06:58 PM
Not to flagellate a deceased equine, but I mentioned firing pin protrusion a while back and it sort of vanished from the discussion. Has it been measured?

Jim

bigbird34
November 13, 2007, 08:17 PM
Yes! Jim it was discussed in my original post app.055" ....at this time I am going to try the 26 lb spring and see what happens,time is on my side (but shooting in the snow does not thrill me:()....I can't check the extractor tension,as the bolt is apart and in a ziplock bag on my desk,to remind me to order a spring .....Wolfe makes after market springs,available thru Midway,so I think I'll order one .....this repair will either be right or wrong ....I'll let you know! Tia Bigbird34

Jimro
November 13, 2007, 08:59 PM
quick way to check if a Mauser firing pin is long enough, pull the bolt, trigger the shroud to go to the "fired" position. Measure pin protrusion with a dime and a nickel. The pin should jut out further than the dime, less than the nickel.

Jimro

Harry Bonar
November 14, 2007, 09:20 PM
Sir:
Gentlemen! There is just something VERY, VERY fishy here! 98 Mausers DO NOT miss-fire unless there is a GREAT DEAL wrong with them!
Check and see if the striker assembly is screwed clear in.
Check the headspace.
Check the caliber.
Get fresh factory ammo!
Firing pin protrusion is .055-.060?
It'll go bang!
Harry B.

Harry Bonar
November 14, 2007, 09:36 PM
Sir:
Are you sure your bolt handle is going CLEAR down? Did someone weld a new one on? If they did that could be the trouble - not being fit all the way down to original level, - that can cause it. Is the handle hitting the wood stock>
Harry B. Something simple is wrong!

Harry Bonar
November 14, 2007, 10:03 PM
Sir:
When you resize your fired brass do you unscrew the striker mechanism and take a sized case, insert it under the extractor and see if when the bolt is closed you have any end-play in the bolt with the case in the chamber - you should FEEL the bolt close on the sized case (NO, NOT A LOADED ROUND!
Harry B.

Unclenick
November 15, 2007, 03:52 PM
Bigbird34.

I was double-checking the specs in Kuhnhausen. He puts the firing pin protrusion spec. between 0.055" minimum and 0.065" maximum and warns of the need to replace any pin with less than 0.055" protrusion. In post number one you said your's was between 0.050" and 0.055". Kuhnhausen is adamant that it needs replacement below the minimum. I would see if I couldn't borrow a depth micrometer and get a more exact measurement? I will speculate that Kuhnhausen's adamance is based not so much on, say, 0.050" protrusion being too litlte for ignition, but that a pin that starts out longer than that and sets back over time is likely losing proper nose contour.

Reviewing Kuhnhausen's misfire list, it also includes any bend in the firing pin, weak spring, excess headspace and an oversize firing pin hole (port) worn into the bolt. He comments that the most accurate rifles have 0.002"-0.003" firing pin port clearance. You will see crater rims (cratering) of your primers if the port is really wide.

Unless I am not seeing it, you have not mentioned what your primers are? About 20 years ago when I first got my Dillon Square Deal, I had to give up on CCI primers with it because it just didn't consistently bottom them out in my cases. The harder military brass cases in particular, even after cutting out the crimp, proved difficult with the slightly harder CCI cups. I hate to recommend a change in priming tool, but if this is your problem, K&M's Markel tool is the only one I know that absolutely positively lets you feel the primer cup touchdown on the brass in the flashhole. The priming tool built into the Forster/Bonanza Co-ax press is the only one I know that positively forces the primer 0.004" below grade, as it were, of the case head. Either tool will make sure your primers are where they should be. Going to a softer cup, such as the Federal primer (generally considered among the most sensitive primers, too), would be another approach to take if you aren't using them already?

The headspace thing still needs to be checked. As a shortcut, you can neck-size-only a few cases and see if that helps?

Nick

bigbird34
November 18, 2007, 10:23 PM
Gentlemen thanks for all of your advice so far....

1).The head space was checked by a gunsmith,all ok.
2).The latest brass tested was all R-P.
3).The primers were this years Winchester L.R. primers.
4).The new 26# spring came in from midway,it is installed in the bolt,and I have fired the firing pin into spent brass primers,and there is a considerable difference in the primer indent (The gun has not fired live ammo yet!).
5).Off to the range Monday or Tuesday ,to test fire ...if it fails, I'll order a new firing pin,as when these missfires first occured,It was brought to my attention that the f.p.'s can wear from hard primers,time,and improper dissasembly and reassembly ...my firing pin measures at the questionable measurement/length .....
6).The new 26# wolf spring was longer then the original by about app.1" and took a little muscle to compress....and in the next 48 or so hours we'll know if I'm a). right,b).wrong.....:D

Thanks again for all your help,Bigbird34

Harry Bonar
November 19, 2007, 04:57 PM
Sirs:
This isn't over yet!
Harry B.

bigbird34
November 29, 2007, 06:43 PM
Well Harry,I love a challenge,and the Mauser is turning into that, "a challenge"....the 26 pond spring was installed and we went to the range and fired the mauser .....I don't like the 26 pound spring ....I fired a 1" group at 100 yards ,but I just don't like that heavy spring ......the rounds that would not fire "fired" ,and the remaining rounds that "I" loaded fired also ...we had one round that would not go off ,no matter what !
So, Based on the information provided by another poster I measured the firing pin protrusion ~.053",still kinda short.....so I took the bolt apart again,and had a machine shop measure the OAL length of the firing pin 7.322"...then on auction arms I found Mauser firing pins for sale and this nice gentlemen had me measure from the shoulder of "MY" firing pin to the end of the firing pin .....his is longer and mine is about .020" of an inch short (Don't tell my wife)....well a new firing pin is on it's way (from Alaska) I'll probably see it in Feb ,so I can go shoot in the snow (NOT) ....
I also started looking at the ole R-P brass I have been using,and once primed the primer is abot.008" of an inch recessed into the primer pocket,again probably more than should be .....so when the new firing pin arrives,and installed ,back to the range with 20 reloads ,and possibly(new factory loads ,OR new factory brass that I reload) (this is up to my son) it's his gun....but there is just not enough time in the day here in the cold north east to do all I need to do ,before we're up to our armpits in snow ,so getting ready for this winter is high on the list now,but I'll keep you all posted on my Mauser adventures .....Happy Holidays,Bigbird34:)

Harry Bonar
November 29, 2007, 09:06 PM
Sir:
Happy new year and have a merry christmas.
I so hope you get your rifle straightened out - I'm sure you will!
It sounds like it shoots well - better than most.

When I seat my primers I don't worry about measuring how deep they go - primers ought to be seated until they "stop" in the pocket - many of us want to "pre-stress" the mixture slightly. In all my primer seating I've never found one seated that way, fail, or be above the face of the cartridge!
And, most important - I want during full length resizing to feel the bolt close on the case! This assures you're at the datun line at the shoulder and against the bolt-face - loads tend to be more accurate that way because you're aligning everything on center. (hopefully). Be sure to keep all of us posted on progress - we'll figure it out.
Harry B.:)

P.S. Really, it doesn't matter if the pin strike is slightly "off-center" - matter of fact that lets the fin go against the anvil.