Winchester .22 RF Low Wall misfire fix

[Snakeoil]

I have not posted about this here. I have a Low Wall made in 1899 that I had rebarrelled with an original lined barrel well over 30 years ago. The smith that did the work was famous for being able to rollmark factory Winchester markings. He came highly recommended and unfortunately, he kinda sucked. When I got the rifle back, it would not fire. Sent it back and told him the extractor was not fitted properly. He was not happy, but fit a new (maybe) extractor. It fires some ammo and clicked on other ammo. I put it in the cabinet and did not touch it again for 20 years. I pulled it out about 5 years ago and found ammo it liked and shot it in chicken shoots. But the accuracy of that Winchester Wildcat was dismal at best.

So, I started using better ammo with the result being first trigger pull, CLICK. Recock, second trigger pull, BANG! Been talking to those with much more experience with High and Low Walls and working thru it on my own. Today I figured it out. Below is a report I sent out to a bunch of Low Wall .22RF shooters I know. Gotta share and file the knowledge away as it floats to the surface, right? So, thought I'd share it here.

Spent several hours with the Low Wall today after yesterday’s dismal results for my first attempt at a fix for the chronic misfiring issue. Giving the extractor a better fit in the extractor groove made no improvement. But yesterday was not a total loss. I tried another little test. I reduced the diameter of the bullets with my pocketknife so they would not engrave the rifling. This allowed the rifle to fire properly in 4 out of 5 tries. And that one misfire was with a bullet that I barely scraped any lead from the driving band.
I was now pretty sure that this was a headspace issue. What was happening was when the bolt was closed, the round was not going all the way home due to the excessive headspace. When the hammer dropped, the firing pin would push the round further into the rifling, thus using up some of the energy/inertia of the hammer to seat the cartridge. When the bullet stopped moving upon rim contact, whatever energy was left was not sufficient to fire the round. A re-cock of the hammer would have the hammer falling on a cartridge that was now hard against the rim in the breech and all the energy went into the firing pin blow to the priming compound and it fired.
So today, with the mainspring removed, I kept closing the bolt with a feeler gauge between the bolt and the breech face. Max allowable headspace is 0.007 inch. I kept moving up in feeler thickness until I got to 0.014 inch and I quit. That’s twice the max headspace.
The standard fix would be to set the barrel back, recut the extractor groove and recut the chamber. That’s a lot of work for a rifle with a lined barrel. There were two possible root causes for the excessive headspace. Either the extractor had too much material removed from the face (it was probably a used extractor) or the groove cut into the breech face was too deep. I’m pretty sure it was the latter, but it could have been a combination of both. I won’t know unless I order a new extractor and compare the two.
With the extractor seated in the relief groove that's cut into the breech face, I could see a slight step where the breech face had not been cut indicating that the extractor was too deep. So, I started measuring the extractor rim relief, the groove in the breech face and that little step. The groove and the step were a bitch to measure so I was not confident in the accuracy. But after repeated measurements and some simple arithmetic, it looked like the extractor needed to move aft about 0.012 inch towards the breech bolt..
So, to confirm this, I took a strip of paper, which is a nominal 0.003 inch and folded it so I had 4 layers, which would be 0.012 inch. I tucked it between the extractor and the extractor groove in the breech face and closed the action. It closed up tight and the toggle had a nice firm over-center feel, locking the bolt closed. Could not get any sized feeler to slip between the face and the bolt. Bingo!!
Dug thru my assortment of flat spring stock. I never throw out anything before disassembling and scavenging it for things like springs, micro-screws, small capacitors, etc. I found a piece of flat spring steel that measured exactly 0.012 inch. Cut a small piece, superglued it to the back of the extractor and reassembled the action. Closed the bolt and it was perfection.
So, took this tiny shim and scribed the cutout for the chamber and removed 99% of the cutout with my Dremel. Then, I cleaned everything and soldered the shim to the back of the extractor. With that done, I cleaned away all the excess solder and put the action together again. Perfect. Then it was just a simple matter of finishing the fit of the chamber cutout and cleaning up the extractor before reassembling the action.
With the gun back together, I went out side to test the rifle. I tried a bunch of different ammo and every round fired on the first pull of the trigger. Looks like the rifle is fixed.
I may order a blank extractor from MVA and fit it to the gun and recut the chamber in the new extractor. But that is not a high priority.
I made a drawing for the fix since a picture is worth 1000 words and attached it here.

 

[Ben]

I have my doubts that you'll ever have another problem with that rifle !
Nice trouble shooting skills, nice work.

Ben

 

[RicinYakima]

That is great!

I am sorry to say that is why I began working on firearms. I had a Sharps cap lock to centerfire conversion that would not fire reliable. When push came to shove, he said it looks beautiful and will chamber a round, it doesn't have to shoot! Never went to another gunsmith that made restorations.

 

[Petrol & Powder]

Excellent work.
If for some reason that shim ever needs to be replaced (highly unlikely) you could just solder a new one in place.

I'm not sure I would buy a replacement extractor and fit it to the gun, your solution may be better.

 

[Snakeoil]

Thanks guys. Think I'm going to go to the local club at put a few on paper today.

 

[Snakeoil]

The range session was less than stellar. First, the temp was 28F when I left the house, and the wind was blowing. Sun being out simply lulled you into thinking it would not be "that bad".

I had one misfire at the range. But all the others fired. Since the PMC ammo is at least 30 years old, it could simply have been a bad primer. The strike was certainly hard enough based upon the divot in the rim.

I started with PMC Target to warm up the barrel and get a sight setting since I had none for my 20X Unertl and this rifle. The PMC Target looked what I have come to expect from PMC. Group was just over 4 MOA. All these targets were shot at 50 yds off a bench with a front and rear rests.


Gave up on the PMC and starting shooting TAC-22 Practice Target Ammo. Things started to look good, but then deteriorated a bit. All 3 targets are shot with TAC-22. Note that there are some really nice sub-groups. But there were always flyers.

It was so stinking cold on the firing line that I only shot the PMC and TAC-22 ammo. I could not feel my fingers and was not having fun. So, I went home. I'll tell you, shooting indoors all winter at Wilton has made me soft. Plus, I was up from 3am to 4am with the new pooch and then again at 6am so I'm a bit tuckered out and grumpy. It could be that the cold weather contributed to my group sizes. Wind should not have been a factor at 50 yds.

 

[Snakeoil]

Well, Muddah Naychah dumped a bunch of snow on us yesterday. We got about 6 inches but Wilton got more like 18 inches or more. I stepped off the firing line and was up to my knees in snow.

Turnout for the .22 silhouette match was small. I had brought my 52C and the Low Wall. But when they decided to not set 3MOA rifle targets and just shoot the standard silhouettes, I decided to shoot the Low Wall. I had my 20X Unertl on the rifle, so not seeing the targets was not a viable excuse should things go badly.

Started at 50 yds and only had a 50 yd scope setting. Shot a really nice group. I was not expecting it to do this well based upon yesterday's test session. 100 yds was equally pleasing with an even better group size. I did struggle to get on the target since I only setting for other rifles with scopes. But after maybe 4 or 5 shots, I was on the target and never missed again.

The light was truly challenging. Sun was out but there were clouds and of course the sun was still rising. When I started on the pigs at 100, neither of us could see my hits on the berm. So, I put a full turn down on the scope thinking I was going over the berm. Next shot cut a nice path in the fresh snow. Took two more shots and adjustments to get on the target. Fired my 10 for score and just about then, I saw this huge hole just above the back of the pig on the snow. It was not there before and was too big to miss. I thought I might have missed while shooting for score, but we both saw the target move each time. Then I looked at my elevation setting and it was a few minutes below where I initially set it to start out on pigs. That big hole must've been where my initial shots were going. Hmmmm. Then Steve shot and as he was taking his last shot on the pigs, he hit the target and it started to swing. The hole was clear as a bell, almost looked black in the snow, but as the target swung, the hanger cast a shadow and the hole completely disappeared. And I was looking thru my spotting scope. So, the light was masking the holes in the snow depending upon their placement and what the sun and clouds were doing.

Turkeys and Rams both cost me one target. Wind had started to pick up and was changing direction and intensity faster than it could be called. It was necessary to read all 3 flags at 50, 100 and 150 to get an idea how to hold for the next shot. The changes could be subtle and if you were not careful, they would push you of the target. My 87 year old partner is showing signs from his surgery in Jan. The anesthesia can have serious negative effects at that age and I see it in him. He struggles to call the wind. He also forgets to call the wind. So, I have to read the flags with one eye and sight with the other. It's good practice anyway.

So, I'm going to hold off on a rebarrel for now. The extractor fix worked fine and not a single misfire today. A 38/40 on a day with changing conditions is quite acceptable. Just gotta keep shooting the rifle to get a long term idea of what its capabilities are and then decide if it needs a rebarreling. Overall, I'm content with the fix and how the rifle shoots. Only additional trigger time will tell if I'll remain content.

 

[Snakeoil]

It's been a few days since I did the fix. Went to the club on Wed for our casual 25 yd offhand chicken shoot. It's 1 shot for each shooter on 10 targets. Closest to the center wins. Target is a standard 50 ft indoor pistol target. No X ring, just a 10 ring. The 10 ring is about 5/8".

Rifle shot great. First shot out of the gun on the first target punched the 10 right out of the center. I was tempted to pack up and go home right then and there. The rifle never failed to fire. But I noticed that the lever was not coming up firmly against the bottom tang every time. The mainspring also bears on that lever, thru the hammer when cocked and then directly on a tang on the lever when the hammer is down. It would have play. I spent about 4 hours in the basement today with the rifle. I must have taken it apart and put it back together a couple of dozen times. I'm getting really good at it. Well, as logic would have it, it was the mod to the extractor that was the root cause. The 0.012" shim was probably about 0.001 or maybe a bit more, too much. Remember I said above that in closing with the modified extractor, it had a nice over-center feel. Well, that was really the breech block dragging on a high spot on the extractor. Well, high spot is probably not accurate. It looks more like it was a false high spot created either by the shim not tight against the extractor when soldered or the groove in the breech face was not uniform. So, a little work with a flat file and stone trimmed it enough so that the block closed without any resistance and now the lever is tight against the receiver ever time. Fired a couple of test rounds and both went bang.

 

[RicinYakima]

Spent many hours hand fitting parts by guess and by golly because there is no one left alive who worked on these. Your did a good job!

 

[Snakeoil]

Spent many hours hand fitting parts by guess and by golly because there is no one left alive who worked on these. Your did a good job!

Thanks. The primary challenge with the Low and High Walls is you cannot see how the parts function relative to each other. You can shine lights into the ends, but you still cannot see it all. I like to use pemanent markers to coat parts and then work the action. Any high spots will present themselves. Then you have to figure out why they are high.

In the case of this rifle, the rub between the extractor and the breechblock felt just like toggle going over-center. And since the lever is a toggle type action, it took a while before I figured out that the over-center was being created by the high spot as the lever had to put more force to push the breechblock up.

I have Vol II of Campbell's book on the rifles. I read Vol I which I borrowed from Charlie's Gun Shop last year. After finishing up this rifle, I decided I did not care what Vol I cost, I was adding it to my library and ordered it. I found a used copy on Amazon in good shape for a reasonable price, which is a little over twice what they cost new when they were published. There are sellers on fleabay trying to get up to 6 times the original price.

 

[RicinYakima]

Printed on paper books are so rare, they will be the next "hot" item.

 

[Snakeoil]

Well, my revisiting the fit-up undid my work. I went to the range on Saturday to do some work on the golf cart and then thought I'd shoot the Low Wall at 200 yds. I had a number of misfires with the PMC target. Today, I removed the extractor and unsoldered the shim. The filing/stoning I'd done to remove the over the center feel, results in the shim being reduced from 0.012 to 0.010. Hardly enough to cause a misfire. This told me I'd missed the true root cause of the issue.

I used to do root cause analysis as a regular part of my job when I was working. I know that the key is to not go into the problem with preconceived notions and let the evidence tell the story. I realize that I was looking for a cause that would allow a relatively simple fix. I broke one of my own rules.

I think I found the root cause today. The cut for the rim in the extractor is within spec from a depth perspective. It measures about 0.044 deep. It's not any easy measurement to take. But I used a depth mic and got repeated readings. Yet, when I put an unfired round in the extractor and measured the distance from the face of the extractor to the base of the cases, I measured between 0.009 to 0.010. The rim thickness of the cartridge was a nominal 0.041. So, the numbers do not add up. The case was sloppy in the extractor cut-out and my assumption is although the depth of the rim cut in the extractor is correct, the width of the cut is too wide and the case goes deeper than it should. This is more evidence supporting that the smith used an old extractor and fit it as best he could to the breech. When I added the shim, which basically made an interference fit between the breech block and the extractor/breech face, it was sufficient to produce reliable primer strikes. But in reality, it was probably on the ragged edge of not working.

I'm back to considering a new barrel. But I'm also considering a new extractor. I need to call MVA. I swear that the extractor I bought 2 years ago was a blank flag shape. But with others saying that they are unobtainium, I'm starting to question my memory. I need to call MVA tomorrow.

The other solution that stumbled thru my brain is to machine a copper cylinder to the min spec of a .22 case and put that into the cut-out and then TIG weld up the rim cutout. They it would be a simply matter of running a reamer into the assembled action to recut the rim cut out to spec.

The rifle is starting to become an obsession. It sat in the cabinet for 30 years and I never gave it much thought. I love my 52C and it shoots way better than I can. But I seem to be under the spell of this low wall and need to make it shoot. All guns should shoot. There is not much I cannot fix. But this one is a challenge for sure.

 

[Snakeoil]

The rimfire extractor is not available from anyone. Only the modern 2-piece is available and will not fit in an original rifle. Grrrrr....

May go over to see my buddy Jake and see what he thinks about TIG welding that extractor as described above. He was a fabricator by trade and is a super welder.

 

[L Ross]

The rimfire extractor is not available from anyone. Only the modern 2-piece is available and will not fit in an original rifle. Grrrrr....

May go over to see my buddy Jake and see what he thinks about TIG welding that extractor as described above. He was a fabricator by trade and is a super welder.

I don't know for sure if Wyoming Armory in Cody is still in business. When they rebuilt my Hi-Wall we agreed to put in an extractor and they kept and gave me credit for my ejector. Maybe they have extractors or know where to get them. I think I dealt with Keith Kilbe there.

 

[Snakeoil]

Talked to them this morning. No gots. Thinking about having them made. Nobody makes them.

 

[Snakeoil]

Spent a good chunk of the last 2 days measuring my extractor and making a drawing. It is a complicated little sucker. Had to set it up in my mill and indicate many surfaces to capture all the angles. Having Keith look at quoting it. Cost to produce will determine if I follow thru with making these.