22PPC difficult extraction

F

Fritz D

Guest
I apologize in advance, this is going to be a long post. I'm not a real bench rest shooter and I don't have a bench rest rifle, but I figure this is a good place to get advice on the PPC cartridge.

In 1988 I purchased a brand new Sako A-1 single shot bolt action in 22PPC USA calibre. I ordered the rifle from a local gunsmith (long out of business). I had problems with the rifle right from the start. Using Sako 22PPC USA factory ammunition extraction was very difficult, requiring the bolt to be struck with the palm of your hand to extract fired cartridges. Handloads (suggested starting loads) are not much better.

I returned the rifle to the gunsmith who requested permission from the importer (Stoeger I assume) to correct the problem. Any improvement was slight. I only fired the rifle a limited amount and then stopped shooting it altogether. I have recently started to do some shooting again and I would like to be able to shoot this rifle.

I recently fired 1 shot from one of the boxes I bought back in 1988 and had the same problem with difficult extraction. To my untrained eye there are no obvious marks on the fired cartridge that look like they could cause extraction difficulties.

I made a chamber cast, the neck portion measures .2535" at the very end, .254" further back. Factory cartridges measure .251" - .252".

I did some experimenting with empty cases after full length resizing (Forster bench rest die). What I noticed is that they chamber/extract without resistance depending on the orientation of the case. I tried this with several cases, rotating them 90° every time I rechambered them. With all the cases I tried, one of the four "rotations" required a bit of force to close the bolt and to extract the case.

I also noticed there is very little clearance between the bolt face recess and the case rims. I blackened the rim on a fired (unsized) case and tried chambering/extracting it, with the "22" on the headstamp oriented at 12, 3, 6 & 9 o'clock. At 6 o'clock the black was scraped off on one side of the rim (around the periphery). In this position, there was noticeable drag closing the bolt, some drag lifting the bolt, and extraction was difficult (I had to whack the bolt with my hand). I tried this test twice with the same results.

The rims on my cases measure .445"-.446". My Hornady manual says rims should measure .441". I have a small lathe and decided to try turning the rim on one case down to .430" and try it. I loaded and fired it 5 times, orienting the case differently on each shot. 3 of the shots extracted perfectly, the other 2 needed a VERY light pull to extract. After I was done this test, I blackened the rim of this case (unsized) and tried chambering/extracting it. The black was not scraped off no matter how I oriented it.

I've received several suggestions on a couple of other forums, this last experiment makes we wonder if the bolt and/or the bolt face recess are not in perfect alignment with the chamber.

I would appreciate any advice or suggestions.
 
One thing comes immediately to............

mind from your description, you may want to very lightly turn the necks to uniform them. I don't have any experience w/the PPC, but I THOUGHT that case had a straight neck. Your measurement of the brass rim disclosed a problem there that would be easier to fix by reducing it as you did, rather than to try to modify the extractor, you can always take it off, BUT...... If you do a search for the threads, there were a number 6-8 mos. ago here, that touched on the rifle you have, and comments about it. Saubier.com may be helpful for you in that regard, as there are many on that forum that shoot these rifles, and love them. Sorry I couldn't be more help. I shoot the little SAKOs and cherish them, but never had one in that caliber. Good Luck.
 
22ppc

Thanks for the reply, I will check out the website you suggested.
 
My limited experience with Sako brass in a Kimber 84HB in 6 PPC left me somewhat less than impressed with its uniformity. The necks varied more than RP or WW .222 and .223 brass I've measured.

You don't have much neck clearance with that brass in that chamber, and one neck a tad thick could make things way more exciting than you'd care to experience.
 
From all you've done, it sounds like you are on the right path. Almost sounds like a "crooked chamber", but your description of a mis-alignment is probably more accurate. I would recommend that you get the rifle & some fired brass to a competent gunsmith for an evaluation. Another thing I would like to contribute is in regards to Lapua brass. Lapua is a good brass to use, but you absolutely MUST turn the necks to have a safe round in the Sako rifles. I have a 6PPC & love it, use the Lapua brass with the necks turned for correct clearance, extremely accurate for a factory rifle. Let us know what you find, please.
 
22 ppc

I have not checked this thread lately, thanks for the replies.

I've done some more measuring of several cases to see if I can find any indication that the chamber may be out of round. Using a caliper set on top of gauge blocks I was able to measure several cases at the exact same point along the case. I took readings at several locations on the case. Other than the taper of the case, none of the readings varied more than approximately .0005".

I have 2 more questions . . .

What would be considered normal case neck to chamber clearance for a production rifle?

Also, I would be curious what the case rims measure (diameter) on the Lapua brass. Could someone please take a measure and let me know?
 
ppc difficult extraction

I would first make sure that the extractor does not protrude above end of bolt. If it does I would hone it down. Second I would make sure they are trimmed to proper length. Sako brass stretches really bad. I have had to trim after firing only once. You should have more than enough clearance on neck. Most shooters have .001 clearance on both sides of neck.
I only used this brass when there was a shortage of PPC brass. I would use Lapua or Norma.
Hope this helps
Best of luck
 
The fastesrt way to determine were the proiblem is by sacrificing one case.Take a case that fits extremely tight in your chamber and cut the entire neck then chamfer what is left so you don't have any burrs.
I seriously doubt this is the problem.
Now cut off the entire shoulder and deburr the case very well to remove the burrs left over from the cutting process.If the case now fits right in without any effort you need to bump the shoulders back.
If it doesn't fit right in your die isn't sizing the area right in front of the web enough so either get a small base die or grind down your full length die about 0.020 and all will be well.
Lynn aka Waterboy
 
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