Quite Proud of myself today, Fixed 2 10/77's

[On/Scene Tactical]

Hey Guys...

I picked up 2 10/77's today from a friend, one a 10/77W (wood stock) that was literally in a ziplock bag of parts, split in half.

The other was assembled and was having serious power problems,,wasn't getting any C02 what so ever...

I started on the bagged 10/77W, and within 2 hours, had the problem fixed and put back together in working order, less the transfer tube seals, as these were shot.

I figured,, I've got one rifle in a bag of parts,, the other assembled.. I may as well experiment, strip it right down, including the valves and learn how it goes back together..
Worst comes to worst,, I'll have a bag of parts,, or I could carefully take the other gun apart and see where the parts go.

What had happened to this gun was the retaining pin for the hammer spring had snapped, it was plastic.Easy fix.

I ground off the remaining plastic pin, marked the general area of the pin, then drilled a small hole. A tiny screw was turned into the hole with a nut on the back and hit with locktight. Now the hammer spring has a decent place to sit, and Very doubtful it would ever break again..

Put it all back together, and she's leaking C02 for the front valve were the tansfer tube enters the valve..
So stripped it all down again, and removed the valve where the C02 cylinder sits against, and disassembled it.

Very easy to do, however you need a wide screw driver..
I used a small tack or nail lifter, as it has a "V" groove in the middle of the blade..Not the proper tool,, but works like a charm...

Removed the bulb seal, cleaned and oiled the screen... The screen was Absolutely filthy, and you could hardly see through it...WD40 and a little rubbing cleaned it right up...

Amazing just how much crap is inside the guns,, Including the valves.

Once I get new seals I'll re-build the valves again...

Now up to this point I had assembled and disassembled the entire works of the gun 5-6 times,, so I'm now pretty much an expert at putting them together again... Quite easy once you know where everything goes..

Hey not too Frigging bad for having a bag of parts, first time handling a 10/77 and not having a diagram Eh ?? !! I knew dropping out of piano lessons would pay off one day! LOL

The second gun with the power problems, was quickly disassembled, and I went staight to the powerlet seating valve to get at the screen (Which BTW someone in another thread had suggested, Thank you,, whoever that was)

The screen was Very dirty,, but not the problem at all..It was the piercing pin...

The peircing pin had a VERY tiny, the size of a needle tip piece of tin from a powerlet stuck in the hole..like a cookie stuck in a cookie cutter..
I simply poked it out with a staight dental pick, and bingo..

Reassembled the gun,, and back in service...Shoots like a charm...

Not the most powerful pellet gun I've ever fired, but fun none the less.

For $50.00(less new seal kits) I've got two perfectly working guns(One with a pretty nice walnut stock) that the kids are going to have a Blast with.

That was alot of fun working on that basket case 10/77.. A little reasoning and trial and error, and thought goes A Long Way Eh !!

If anyone has a 10/77 that needs to be put back together,, let me know,, I'll explain how to do it..When I get the seal kits, I'll try to do a little picture "How To" Quite simple actually..

Thanks for the Encouragement and suggestions in the other thread Guys!

ttyle

Eric....

[sniper]

Hi Eric,
Congratulation ..... you got it ..... excellent ...
a little bit of mod that 1077 should be in 500......+

[On/Scene Tactical]

Hey Sniper..

Thanks!!

Power Mod?
Did someone say Power Mod? Power Mod!

LOL

Ok,, so how does one power mod a 10/77..
I'm All ears!!!

ttyle

Eric....

[ABshooter]

Hey Sniper..

Thanks!!

Power Mod?
Did someone say Power Mod? Power Mod!

LOL

Ok,, so how does one power mod a 10/77..
I'm All ears!!!

ttyle

Eric....

Well, I've never had a 1077, but you could put a light spring in the valve, and a heavy spring behind the hammer. That would get you more power but less shot per powerlet.

[jimi]

sounds like fun. Ill have to check them out.


cya
jimi

[sniper]

Ok,, so how does one power mod a 10/77..
I'm All ears!!!

ttyle

Eric....

Take the valve apart, replace the spring with a lighter one, and just drill the transfer port a bit bigger ..... that's all ....

[On/Scene Tactical]

Hey Sniper..

That would probably work...

However they have a Strange valve system in the..
It's a two part valve with a piece of tubing in between...

Any changes to the exhaust port would F up the seals of the transfer tube...

It would be a bit of a job i think...

Hammer and Valve spring could be do-able..
however,, you have to watch out for the hammer spring as it sits on a plastic post...

The post is pretty cheap to begin with,,so it should be Modded the way I made the mod on mine before a heavy hammer spring is installed..

Easy mod,, simply cut the hammer spring post off.. grind it flat, drill a hole and put a tiny screw and nut in the posts place..Re-install the spring into the new screw/post...

Thanks

Eric...

[ancorp]

Eric,

Sorry to resurrect this thread, but it sounds like you are just the person I need to talk to.
I recently aquired a 1077 locally that leaked gas. ($15 with 5 clips and a mag!!! hehe)
So, after taking it apart, and putting in yet another powerlet, the gas was hissing from the end of the tube, the end that connects to the piercing valve... I noticed it was loose as soon as I took it apart...

...and than it popped off and flew accross the table (the main valve and the tube attached to it).

What Im curious about is how to open up that piercing valve, and how to reattach that tube. No damage seems to be done on the tube...

Thanks!
I appreciate any help I can get

Cheers!
Alex

[On/Scene Tactical]

Hey Alex...

No problem at all.. Glad to help out and hopefully give back to this excellent wealth of information and forum...


Ok,,well first thing is first...If it's sat around for awhile and is leaking gas, the seals are surely dried out...

Complete seals need to be replaced, and they are about $3.50 for the kit from D&L..

Ok,, once you have the casing split, remove the barell assembly...

You will notice that the back end of the gas tube has a roll pin in it..
Attach a pair of vise grips,,Very tightly to the roll pin and twist it out.

The piercing part of the valve easily comes out after that..

At the piercing cap, you will notice a slotted screw...I didn't have a special tool for this,, but was able to unscrew it using a slotted tack lifter..Kind of like a very wide bent flat head screw driver with a slot in the middle...

You can pick up a tack lifter easily at a hardware store,, or simply make one from something..A specific tool would be best,, but this will work in a pinch...

Carefully remove everything clean the screen, replace two seals and reinstall..
Fairly simple once you see how it goes together..

Amazing that those things don't leak right out of the box.. A fairly crappy way of transfering gas from one valve to the next..

If you want,, while you've got it apart,, do the hammer spring post Mod on the rifle. Simple,, easy to do and save you a headache in the long run..

Any questions,,please feel free to post or email me..

ericn@mnsi.net

Hopefully that helps..

ttyle

Eric...


[

[ancorp]

Hey Eric,

Thanks for the quick reply!
Damn thats a nice writeup

I think its best if we talk here, so the next person with this problem can get a good read.

So - first thing's first - I need new seals. Are any available locally? (around Toronto, Ontario)... if not, I cant seem to find the kit on D & L's website...

Also the hammer spring post Mod... how?

And would it be difficult to put in the roll pin back? Any special tools needed?

Thats it, so far atleast.

Thank you very much for you help, I really appreciate it!!!

Cheers!
Alex

[ancorp]

Cheers,
Alex

[ABshooter]

Hey Guys...

I picked up 2 10/77's today from a friend, one a 10/77W (wood stock) that was literally in a ziplock bag of parts, split in half.

Does that mean the stock is split in half?

[On/Scene Tactical]

Hey Guys...

AB..

No the stock is in one piece..The reciever housings were split.


Alex....

Thanks..

Seals can be had from D&L..I think they are like $3.50 a set..
If I'm correct,, there should only be about 4-6 parts to the seal kit, depending on what they supply...

When you split the casing,, you will see a 2 piece valve with brass tubing in between...

On the upper valve the only seal that needs to be replaced is where the brass tubing goes in..A little black seal...

To remove the roll pin,, just hook up to it with a pair of decent vise grips.. It will easily twist out,, and go in pretty much the same way it canme out..You can tap it back into place..
Just pay attention to how much was sticking out...

There should be 3-4 parts inside the bottom valve that is replaced...

Once you remove the large slotted screw where the C02 cylinder sits,, there are several parts in there.

C02 seating seal, another small round I believe plastic part, a screen, and another small black seal that sits on top where the brass tubing goes.

Be careful when you take it apart,as there as some small pieces that easily roll/bounce away. Strip it down on a towel,,and watch how it comes apart...

Hammer spring mod is quite simple...

You'll need a drill of some sort,, and a tiny screw nut, and lock washer.If no lock washer,, just hose it down with lok-tite.

Where the hammer spring hooks onto a plastic post, on the left side of the housing, cut the post off, and grind the nub flat with the casing..
Mark with a center punch and drill your hole...

Install the screw,lock washer and nut,and tighten...
If you wish, you can add a small washer behind the head of the screw on the outside of the casing..You should use a pan head screw, that is flat where it meets the casing..This will give it fairly decent strength.

Hammer spring now sits on this screw instead of the fragile plastic post.

Very simple mod.

When you take it apart and re-assemble.. you should have the left hand side of the casing on the bench...
Remove the right cover,,and most of the guts will stay in place..
Hold the trigger down as you pry the casing off..

Theres not really that many parts inside,, but you should take note where they go..
A very important piece you need to watch out for is the small silver flapper and pin..These are located right in front of the upper valve, in between the hammer and upper valve..Pay close attention to how these are sitting...

The parts, come out and go back in Really easy once you know where they go..Everything kind of just sits there in the left side casing.When you close the casing back up,, just put the right casing back on,,and kind of wiggle/squeeze back into place..

(To make things easier,, put the left hand side casing screw in the holds the barell in place.. This will keep the barell from moving around too much...)

Hold it together while you get a couple screws in..

Shouldn't take you long once you see how it's put together...
When I did mine I had no instructions or diagrams to go by..If I didn't get it together,, I would have taken the second gun apart to see where the guts all went..
Be careful,, go slow and pay attention...

any problems,, drop me a note..

ttyle

Eric...

[ancorp]

Hey Eric,

Thank you VERY much for such a long reply

I have already taken apart the gun, and put most of it back together, just havent touched the valves, so those tips will come quite in handy!

One thing - why would I need to replace seals in the upper valve? Everything seems fine with the gun, the lower valve just disconnected from the pipe, and I need to know how to attach it back securely. I will take apart the lower valve and see what I can come up with...

The seals are sold seperately at $3.50 each, so it can be quite expensive if I start replacing all the seals (well expensive compared to the $15 on the gun ) I think I just need the small black seal that seals the tube and the lower valve...

I will get into it sometime this week, maybe even tonight.

Thank you! I will keep you updated

Cheers,
Alex

[On/Scene Tactical]

Hey Alex....

Well as far as replacing the valve seals.. While you are in there you may as well do the entire gun...
The seals are $3.50 per set,, not $3.50 ea. So it is Very cheap to replace all the seals.. No sense taking it apart again..

Not only that..If the gun has been sitting for awhile the seals may have gone bad...

Do it once and do it right is what I always try to do...

Kind of like replacing spark plug wires on a car and leaving the old spark plugs in..While your dicking around with it,,may as well do it all...

You also may want to put a little lube on the rails where the trigger slides back and forth...

ttyle

Eric....