Canadian Airgun Forum

Have an up-coming project similar to a previous effort involving a 2200 tube and 13-XX internals. This one will be in .22. It will end up wearing the P-rod grip frame and trigger group, and will require a non-waisted hammer.

I started tonight with a 5/8" dia 1/2 h.p. electric motor shaft in stainless.



There's the piece of shaft before machining. I had to turn it down by .0035 so it would fit in a 13-XX tube. I'll say it here, so it won't have to be repeated: that stainless is a #@$& and +#$%!!%&! to machine. It took me almost 2 hours to take a little over 3 one thousandths of an inch off the diameter. Thankfully I have access to a just slightly wonky Asian drill press, and a good supply of aluminum oxide abrasives.



There it is turned down to dia, first polished and machining operations commenced, with a stock 13-XX hammer for comparison...



I plan on using the keyway groove for the p-rod sear. I'm convinced this will work~ I have an old Crosman 117 here that ran on bulkfill c/o-2, and had a similar replacement hammer inside it, albeit with a larger diameter.



Believe it or not, run-out on the drill press is visible here. Give-away's the slightly elliptic, off-centre hole. I've done worse, and function will be as good as normal.

If there's time tomorrow night, I'll start on the 10X24 tpi hammer pin...

-D.S.

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"Ain't no half-way"
-S.R.V.

Nice work Doc! Yes, stainless steel can be a pain in the lower back area to turn

Do you think the keyway will help with sear drag? I'm asking because I made a hammer (in O1 steel) with a keyway for a 2240 project, not tested yet.

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If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

I think the keyway will help. Set up on the old rifle had the keyway passing over the sear on a 160 style trigger group. It is one of the easiest cocking Crosmans I have. Trigger on it was still heavy, but very clean breaking with an almost audible "snap".

I should test first on the 13-XX tube before I start on the pin, just to make sure the keyway is low enough for the gun to cock. I'm fairly certain it will.

-D.S.

_________________
"Ain't no half-way"
-S.R.V.

Great work! Looking forward to your project [emoji846]

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Website: https://airgunarcheryfun.ca/

Let me understand.... are you planning on having the sear run in the keyway?.... If so, what will latch the hammer back when you cock the gun?.... The sear only protrudes a rather sort distance inside a tube with a 0.065" wall, like the PRod, Disco, 22XX or 13XX tubes.... If you use one on an MRod tube, with a 0.095" wall, you need to either use a taller sear, or machine the top of the trigger group (or the bottom of the tube) so that the sear protrudes a safe distance inside.... Since the keyway is more than 1/32" in depth, what part of the hammer will the sear catch on?....

Bob

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Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!

Nice work, Doc….LOTS of elbow grease involved, but it came out looking great!

I could very well be wrong, but I would be leery using that keyway slot over the sear, though. Sear doesn’t protrude very far into the tube as it is (it was, after all, designed to work with a cylindrical, full-diameter hammer) & I’d be worried that sear engagement with hammer would be minimal at best. How deep is the slot?

EDIT - Bob beat me to it...posted while I s-l-o-w-l-y type

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Cheers,
Todd

I made mine with the slot in the rear portion only, the head is full, like a regular 2240 hammer head, because I suspected that could be an issue.

_________________
If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

Your hammer w/slot will work fine with no issues on an M-rod trigger (that's exactly how I did my hammer for M-rod trigger also), but if you use it with a P-rod trigger group you will most likely have to squeeze the trigger every time before/while cocking it. Just a heads-up...

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Cheers,
Todd

^X2.... The PRod sear pops up and locks in position after firing if it can (eg. waist or slot).... and you then have to pull the trigger to cock the gun....

Bob

_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!

Actually the p-rod hammer has quite a generous amount of milling off its bottom.

It is not a complete cylinder as stated above...

Will check function tonight before I go any further .

_D.S.

_________________
"Ain't no half-way"
-S.R.V.

Is not the PRod hammer milled on the sides, not the top and bottom?....

Bob

_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal; Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!

I'll pull the p-rod hammer tonight. I think Bob may be correct on the sides being milled. I sometimes operate from some what hazy memory....

D.S

_________________
"Ain't no half-way"
-S.R.V.

You guys saved me a lot of work.

Just tried passing the hammer over the p-rod sear in a 13 XX tube. It almost works- it will cock,but it's pretty iffy.
There is not very much for the sear to bite against. Keyway slot is actually a bit less than 5/64", but it is still a risky proposition based on what I can see in the tube.

I can just simply rotate the hammer 45 degrees in the tube and have it work normally.

The P-rod hammer is milled on the sides to clear the breech mount bolts

On the phone and the embarassed emoticon is too to tiny to get at.

_________________
"Ain't no half-way"
-S.R.V.

O.k. at home and on computer.



Got the pin done, with the keyway slot rotated off to the side, well away from the sear. Had a hard time getting the tap to bite into the stainless. Resorted to using the d/p chuck, and rotating by hand, with a fair amount of weight on the d/p actuating lever to start the threads. Cutting oil is an absolute necessity to thread this stuff. The titanium coated drill bits walked through it fairly easily. The motor that the shaft came out of has a '79 date code on it~ almost 40 years old.

I installed the hammer in the parts carbine eluded to elsewhere. Cocking is very smooth, much more so than I expected. Let off is very good too. I'll run the carbine over the chrony Tuesday night, just for the sake of comparison.

It will soon be time to start the 2200 project...

-D.S.

_________________
"Ain't no half-way"
-S.R.V.

Nice! Glad it all worked out well

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Website: https://airgunarcheryfun.ca/