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lampy · Veteran Member

I'm working on my "Home Brew .177" I'm not quite done with it and already looking for another project. I have a bid on a couple fixer uppers, I'll know tomorrow if I won them. I also have an idea for another build, reverse engineer a Crosman 101 and build one completely from scratch. I was just wondering what everyone else is doing or has planned. Do you have a project in the works or plans to start one? Are you looking at purchasing a new or used airgun? What are you guys doing, thinking ?

garththomas · Veteran Member

I am trying to get my Canadian version Diana280 to run at 12fpe, I am embarrassed by the poor choices I've made. First off I purchased a spring and piston from Chambers gun spares that should have given me what I wanted, they didn't I was getting just over 9fpe. Then on an impulse I ordered from airgun artisans a spring that although it had the correct amount of coils it was too small a diameter to fit the guide. While I was mourning that decision I noticed on some photos by someone in the UK who was tuning said rifle that my newly acquired piston was different from his, in fact it looked like the Canadian piston, so since I had tried the Chambers spring with the Can. piston when I first got it and it wouldn't cock I decided to clip a few coils to match the 31.5 that was spec.ed by Diana when I had asked earlier, no luck. So now I've ordered the stock replacement size for a Diana34 from Vortek which just happens to be the same size quoted to me by Diana.
It should be here early next week and if it turns out then I will have wasted $150.00 for this learning experience. There, I feel better now.

lampy · Veteran Member

robert w · Senior Member

I'm about to buy a kit from arh for my newly traded for early beeman R1.it hasn't been shot much but looking at the shape of the spring I'd say it sat cocked for a long long time.no spring load on the end cap.screws off and actually is loose when you try moving it through the slots in the reciever tube.when I traded for it I kinda had an idea it needed help and made sure I didn't sink a fortune in it

Mike Lanum · Banned

My new marauder finally arrived and I got to shoot it a little today. Got the scope shooting 1 groups at 25 yards right now. Still playing around with it to see what it likes to shoot. I'll be running it over the chrony as soon as the weather straightens out a little. Once that's done I'll see about adjusting the power to see how good it can get. Definitely going to be sweet talking the wife into buying me a tank to fill it with. Bad back ain't going to get any better with pumping it up all the time.

garththomas · Veteran Member

The spring I ordered from Vortek is painfully making it's way through the USPS system. Its funny that for the amount they charged for shipping compared to Airgun artisans it should only take a couple days. $25 vs. $10

DavidSaunders · Veteran Member

I am working on modifying one Daisy 922, and one Daisy 880 (metal receiver) for improved power and accuracy. Kind of like I did with my newer Daisy 880's and 22X already.

I am also making new seals for my Crosman 101, including the leather piston seal.

Next up is modifying my Dasiy 953 for better accuracy, and a very slight bump in power. Though first I will do the trigger mods to improve that issue.

garththomas · Veteran Member

I have been also working on my XS B50, after Rsterne finally got his 51 out to tinker with it rekindled the fire to make mine an honest 12fpe gun. I did some of the valve work, reshaped the poppet and replaced the factory washer with a thinner one and drilled the transfer port on the valve itself a little larger. I did that to make the valve hopefully more efficient so then any tuning efforts would be controlled by using a lighter hammer spring and tophat as well as removing preload, changing the transfer port size and then if I really had to I could extend the striker screw.
I guess it was a success, I got the shot string to peak at or just above 11.5fpe. I first thought I would aim for 11.9 but after a while I realized that working with in 1/2fpe is about 10fps difference and I am not sure how close field target people have to be to 12 but apparently its a major crime to go over in the U.K. I also during this exercise began to notice a correlation between the speed variation from shot to shot and how hard I had to push the pellet home when loading so I stopped at 11.5fpe max. Do I have a full shot string to show for my troubles? No. I must have used up over 500 pellets and in the process while trying to figure out ideal fill pressure I had to rebuild my hand pump and dealt with a few other errors I made in procedure to the point of I don't care anymore! I've also come to the conclusion that I don't want a 12fpe .22 maybe a .177 for targets but to do the nasty I will stay in the 15fpe range. Sorry for the lack of detail but if your interested shoot me a question.

lampy · Veteran Member

I started this thread out of curiosity, and I'm always looking for inspiration for future projects. Sometimes all it takes is one comment to get the wheels turning and a new project is born.
Thanks for sharing.

rsterne · Moderator

I'm currently converting an XS-60c to a .30 cal regulated HPA repeater.... Next up is installing a 7mm barrel on my Hayabusa....

Bob

lampy · Veteran Member

Slavia · Moderator

I have a 1377 carbine conversion in progress. There is also a Marksman 1010 that now has a rifled barrel, but needs a different seal design. The HW97 hasn't been opened yet, and there are some things in there I want to polish. I need to refinish the 853 stock. I also have a B3 that's supposed to be the "before and after" mate to my other two modded B3's. Who knows how long that will last.

Bob La Londe · Veteran Member

Wheeeeell! I had planned on bottling my .25 Marauder by now, but the custom mold making has picked up lately and I haven't had the time. Communication contracting has picked up a little bit too and that's putting time constraints on mold making. LOL.

I suppose my next gun room project needs to be finding and fixing the leak in the regulated .177 Marauder. It drops down below regulator pressure in about a week.

Robw · Veteran Member

Right now I am waiting on a 10mm barrel for a 800cc Condor Elk rifle I have
been working on for almost two years.

I am also building a 1322 I received as a Christmas gift.

So far I have enlarged the compression chamber, installed a very weak valve
spring, The front portion is aluminum that I TIG welded the intake port shut
and re-drilled a slightly smaller diameter one to decrease head-space
a smidgen.

I was inspired by rsterne to shave a little off of the cone on the front of the
compression chamber as opposed to a flat-top piston. He was spot on with
that one as it was the modification that improved power output the most.

I used a brass rear compression chamber half because the exhaust valve
shaft slides easier and is less likely to bind and induce chattering (which
slows exhaust valve travel). If you use this combination be sure and use
some aluminum particle lithium soap based anti-seize compound as the
front aluminum half will galvanically weld together with the rear brass
half in time. The exhaust valve shaft was contoured where it passes through
the air path. This increased velocity only slightly, but greatly decreased
velocity spread. The first thing that I did with the back half of the
compression chamber was to braze the exhaust port closed and re-drill at a
40° angle. I kept the same diameter as OEM though.

Oh, and I have set this pistol up to be permanently lubed. No oil is needed
for quite some time. Everything is lubricated with Moly grease.
The piston is stuffed with grease saturated foam. I did this because in the
past I have built some pumpers that people tend to over lubricate. I am
hoping that at least some of my customers will not over lube their pistols.
I get some returned for power loss only to open them up and discover that
they have been over lubed to the point of washing grease into
the compression chamber where it takes up space that I have hogged out to
increase chamber volume thereby rendering my work moot.

The barrel is the original with an 11° crown and choked the last half inch.
So far with Crosman pointed 14.3gr it is producing 511fps @ 10 pumps,
582 @ 12, 607 @ 15, 617 @ 20 and 622 @ 25 pumps.
I usually shoot it at 15 as pumping it 20 times wore piston out in a month
and a half. It is the most accurate @ 12.

The trigger group is a two stage 4-lever, two sear arrangement.
All of the springs are foam filled with the exception of the safety spring which
has been Teflon velocity tarred just to make it easier to keep track of.

It was kind of top heavy so I also filled the grips with lead to balance it.

Still to come...

-17" Lothar Walther barrel.
-Front receiver tie-down struts. (eliminating tiny front receiver screw).
This will allow me to float the barrel.
-I am also going to be testing a rubber/lead adjustable barrel weight for
adjusting barrel harmonics.

DavidSaunders · Veteran Member

Well now I am working on making two long pump tubes for the 13xx. One to go on my 2289, and one for a friends 1322.

They are designed to use the Crosman 140/101/1400 linkage and piston. So I guess they would be Medium Length Tube Crosman 1322's (or 1322MLT) when done. I am working from some good steel stock material to make the tubes, and pistons, the linkages are standard replacement linkages for the 140/1400.

I am also working on a .22 cal barrel Daisy 880 with power tunes and a LW barrel for another friend.

Then I am working on my own design of blow open valve for the 13xx series.

And lastly I am working on a drop sear, trigger assembly, for the Crosman 140/1400 that use the modular trigger. This so the trigger can be tolerable at higher pump counts.

And who knows what next months list will be. We shall see.