Crosman Town & Country 107

[DT Fletcher]

Yes this morning I went the "easy way" by using the 108 pump arm as an example.
As this didn't work, I will have to follow your, ped's and DTFletcher's info to find the correct length.
I'll get there in the end...

Setting the pump arm length is one of the simplest task to accomplish with these guns. Not sure why you're trying to make it complicated. There is only one way to set the pump length and that is the factory way, as has already been described; i.e. to the point where the pump arm over toggles (some incorrectly call this camming) and leave it there. There is simply no point in obsessing about the air hole. In my entire career of repairing these guns, I never once came across a problem with the air hole. I never even look at it since there's no reason. After all, what are you going to do about it? Drill another hole? You can't adjust the pump arm length to accommodate, since you end up with a gun that doesn't function properly.

As I've tried to explain, if that hole isn't doing it's job, the gun simply will not pump up. In short: stop worrying about the air hole!

As for the low power, the first thing to check is the pump head washer; if the pump head washer leaks at high pressure then the gun will not fully pump up and the power will be low. Very few other things can cause that. So, I suggest getting a replacement pump head of the original style with a new pump head washer.

[--ped--]

personally think the original seals are crap and would only use to keep it original and tbh I'd even then not fit it but have it so it could be returned to original
with modern materials and methods I'd fit an o ring conversion
as to the terminology of the action of the lever locking against tube i'll still call it camming over despite what anyone says as the action is more akin to that as a toggle goes through a loop to fasten two items together

[jirushi]

personally think the original seals are crap and would only use to keep it original and tbh I'd even then not fit it but have it so it could be returned to original
with modern materials and methods I'd fit an o ring conversion
as to the terminology of the action of the lever locking against tube i'll still call it camming over despite what anyone says as the action is more akin to that as a toggle goes through a loop to fasten two items together

Hi ped I bought 2 pump arms with leather seals from JH Airguns yesterday. I shall be sending one of them to you if that is ok
As a part exchange for one of your o-ring conversions.
Would be fantastic. If you want me to order other things from them for you, please let me know per pm.

Thank you DTFletcher for the advice. I will adjust the pump arm length later and stop focussing on the air hole

[45flint]

Toggle in the dictionary:
a device consisting of two bars jointed together end to end but not in line so that when a force is applied to the joint tending to straighten it pressure will be exerted on the parts adjacent or fixed to the outer ends of the bars.

I think DT got this one.

[--ped--]

maybe not Steve
Dictionary

toggle


/ˈtɒɡ(ə)l/
noun

noun: toggle; plural noun: toggles; noun: toggle switch; plural noun: toggle switches; noun: toggle key; plural noun: toggle keys
1.
a short rod of wood or plastic sewn to one side of a coat or other garment, pushed through a hole or loop on the other side and twisted so as to act as a fastener.
•a pin or other crosspiece put through the eye of a rope or a link of a chain to keep it in place.

•a kind of wall fastener for use on open-backed plasterboard, having a part that springs open or turns through 90° after it is inserted so as to prevent withdrawal.
noun: toggle bolt; plural noun: toggle bolts

•a movable pivoted crosspiece acting as a barb on a harpoon.
2.
Computing
a key or command that is operated the same way but with opposite effect on successive occasions.
verb

verb: toggle; 3rd person present: toggles; past tense: toggled; past participle: toggled; gerund or present participle: toggling
1.
Computing
switch from one effect, feature, or state to another by using a toggle.
"the play/pause button toggles between those functions"
2.
provide or fasten with a toggle or toggles.
"our horses were hobbled or toggled before they were turned out to graze"
Cambridge English Dictionary
https://dictionary.cambridge.org/dic...english/toggle
toggle definition: 1. a small bar of wood or plastic that is used to fasten something by being put through a hole or loop 2. a key or button on a computer
now it maybe a US meaning but there again you lads call jam jelly and crisps chips and chips fries

[45flint]

maybe not Steve
Dictionary

toggle


/ˈtɒɡ(ə)l/
noun

noun: toggle; plural noun: toggles; noun: toggle switch; plural noun: toggle switches; noun: toggle key; plural noun: toggle keys
1.
a short rod of wood or plastic sewn to one side of a coat or other garment, pushed through a hole or loop on the other side and twisted so as to act as a fastener.
•a pin or other crosspiece put through the eye of a rope or a link of a chain to keep it in place.

•a kind of wall fastener for use on open-backed plasterboard, having a part that springs open or turns through 90° after it is inserted so as to prevent withdrawal.
noun: toggle bolt; plural noun: toggle bolts

•a movable pivoted crosspiece acting as a barb on a harpoon.
2.
Computing
a key or command that is operated the same way but with opposite effect on successive occasions.
verb

verb: toggle; 3rd person present: toggles; past tense: toggled; past participle: toggled; gerund or present participle: toggling
1.
Computing
switch from one effect, feature, or state to another by using a toggle.
"the play/pause button toggles between those functions"
2.
provide or fasten with a toggle or toggles.
"our horses were hobbled or toggled before they were turned out to graze"
Cambridge English Dictionary
https://dictionary.cambridge.org/dic...english/toggle
toggle definition: 1. a small bar of wood or plastic that is used to fasten something by being put through a hole or loop 2. a key or button on a computer
now it maybe a US meaning but there again you lads call jam jelly and crisps chips and chips fries

You English and your English! Lol.

[DT Fletcher]

It's not that I have this, it's that Crosman Arms Engineering has it. Over toggling is the expression that Crosman Engineering uses to describe this. Because of that, and only because of that, imho, it's the only acceptable term to use. There is simply no need for any other way to describe this. And, to add other terms, serves only to confuse folks who are perhaps not clear on the concept and hearing conflicting terms to describe the same thing never helps.

Should perhaps add a bit of history on "over toggling" to provide some perspective. The over toggling concept goes back to 1925 and the disaster of the first Crosman Arms model with a forearm lever pump; usually known as the "transition" model in that it came after the 1924 model and just before the well-known "101" model that first appeared in the 2nd half of 1925. What made the "transition" model a disaster was the way the forearm was held up: by a spring-loaded detent ball in the receiver. The problem being that the small, but constant, impact of that spring detent invariably broke the die cast front sight assembly.

The answer that saved the fledgling Crosman Arms and their innovative but flawed design was...... over toggling the pump bolt. Which makes the term "over toggling" 93 years old.

[DT Fletcher]

Hi ped I bought 2 pump arms with leather seals from JH Airguns yesterday. I shall be sending one of them to you if that is ok
As a part exchange for one of your o-ring conversions.
Would be fantastic. If you want me to order other things from them for you, please let me know per pm.

Thank you DTFletcher for the advice. I will adjust the pump arm length later and stop focussing on the air hole

Well, to adjust your pump arm without proper over toggling would result in a "droopy" forearm lever... which I cannot abide. ;-)

[DT Fletcher]

personally think the original seals are crap and would only use to keep it original and tbh I'd even then not fit it but have it so it could be returned to original
with modern materials and methods I'd fit an o ring conversion
as to the terminology of the action of the lever locking against tube i'll still call it camming over despite what anyone says as the action is more akin to that as a toggle goes through a loop to fasten two items together

Original seals crap? Completely agree. They do work but that's about it. I strongly support the fitting of a modern design valve with modern materials. Hell, I'd even go for modifying the exhaust body. There's nothing special about the T/C exhaust body; it's exactly the same as all the others in the class.

[jirushi]

Well, to adjust your pump arm without proper over toggling would result in a "droopy" forearm lever... which I cannot abide. ;-)

The forearm lever is still droopy hehe.
Tonight I finally had some time to work on the 107 again, after all the Christmas parties.
I have the (man?) flu, so I will have plenty of airgun tinkering time

Right, I tested several pump rod length settings.
Greater length, even past the point where the air hole "works", still wouldn't cause over toggling.
Whilst closing the pump arm, I could still see movement of the pump rod, which I think means that it hadn't hit the valve wall yet.
When there's no air in the valve, the pump doesn't stay in place.
After 1 pump, with the gun being cocked (so that air stays in the valve), the pump arm does actually stay in place.
Is the air bubble in front of the pump cup giving the required contra pressure for over toggling to happen?
I also wondered if there might have been a ring in front of the valve wall, when the gun was built? A ring that makes contact with the pump cup, so that over toggling takes place? I don't know.

What I do know is that the maximum velocity that I found previously, 545 ft/s with 8 pumps, is the maximum velocity that I have found today too. Exactly 545 ft/s again. Will try lapping the probe at some point. For now I'm ok with the droopy lever, it doesn't affect my masculinity too much
One last question that I have: in the pump arm assy, there is a spring. Does the strength of this spring have any effect on the pump arm closing ability?

Oh, in DT Fletcher's book "The Literature of Crosman", there are some great photos of T&C ads and of General Hinds and Mr. P. Y. Hahn looking at the new T&C rifle.
I'm not sure if I may share them on here though.

[45flint]

I checked my 108 and forgot that there is a leaf spring inside the cocking arm that supports it as it closes. Maybe that spring is stuck or damaged? On my 101’s as well. I think they eventually did away with these but have no idea when. 545 FPS isn’t out of line?

[jirushi]

Yes I have a feeling that the leaf spring in my 107 pump arm needs to be replaced. It doesn't appear to be stuck or damaged, but it might just be weakened by use and time?
I agree, 545 is nice. In .177, that means a pretty good plinking range.

[DT Fletcher]

It can be difficult to gauge proper pump setting with the internals (exhaust valve, etc) working; which is why I usually set the pump while the internal components are still out. However, what can be done is to take down the gun to the point that you can access the exhaust valve and simply press it in while setting the pump head space. With no back pressure, it's easy to feel when the pump head hits the compression chamber.

Yes, the air pressure left in the air space from an improperly adjusted pump will hold up the pump arm.

Pump arm droop is a clear indication that the gun is improperly adjusted and will not -cannot- operate to full potential. Plus, it's embarrassing.

[--ped--]

an easy way to rough set the piston so it cams over is to get a bit of 1/2" dowell or rod and in sert it down the compression tube till it hits the valve
then mark the rod through the lever pivot pin hole
once removed fit the piston to the rod line the pivot pin hole up on the rod and lever and adjust the piston till it's flush with the end of the rod or a mm longer to allow for wear in the linkages
tis will give you a starting point
another tip is to use a 3/16" punch in place of the roll pin
the spring steel in the lever is designed to keep the lever up with no air pressure and was later swapped to a plastic button in the lever that used friction between the two parts of the lever
Sheridan and Benjamin kept using the spring steel in the lever as they stopped using an adjustable piston rod in the early 60's(sheridans not sure on date for when Benjamin did)

[45flint]

an easy way to rough set the piston so it cams over is to get a bit of 1/2" dowell or rod and in sert it down the compression tube till it hits the valve
then mark the rod through the lever pivot pin hole
once removed fit the piston to the rod line the pivot pin hole up on the rod and lever and adjust the piston till it's flush with the end of the rod or a mm longer to allow for wear in the linkages
tis will give you a starting point
another tip is to use a 3/16" punch in place of the roll pin
the spring steel in the lever is designed to keep the lever up with no air pressure and was later swapped to a plastic button in the lever that used friction between the two parts of the lever
Sheridan and Benjamin kept using the spring steel in the lever as they stopped using an adjustable piston rod in the early 60's(sheridans not sure on date for when Benjamin did)

Thanks for that, I have a new pump rod coming and my old one is already off.