Click Here for AirGunHome.com Main Page AirGunHome.com: THE Worldwide Airgun Forum

Air Gun Home Forum Index » Rifles » One more project    View previous topic :: View next topic  One more project   Posted: Sat Feb 07, 2026 6:04 pm Old Lampy Member Joined: 23 Dec 2025 Posts: 39 Another project I started a decade ago... .22 cal Crosman barrel The trigger group is based on the Crosman 2100. The pump and valve are Crosman also. I smoothed out a few rough edges and added a scope. No Chrony numbers yet. I am hoping to get to the range and get it sighted in and shoot some groups soon. I ordered an LW .25 cal barrel blank a couple days ago and depending on how this turns out I might swap out the .22 barrel for the .25. _________________ "Where ever you go... There you are." Buckaroo Banzai 1984   Posted: Sun Feb 08, 2026 3:38 pm Old Lampy Member Joined: 23 Dec 2025 Posts: 39 After some mods to the hammer spring I got out the Chrony. Shooting CPHP gave me these numbers 2 pumps 340 fps 4 pumps 409 fps 6 pumps 549 fps 8 pumps 610 fps 10 pumps 615 fps Not bad, the valve can't dump all the air starting at 6 pumps. It's a small amount, just the lightest puff and that doesn't change much all the way through 10 pumps. Looks like 8 pumps is a good place to stop. _________________ "Where ever you go... There you are." Buckaroo Banzai 1984   Posted: Sun Feb 08, 2026 5:34 pm AirGunEric Site Admin Joined: 20 Jan 2007 Posts: 6929 Location: "Out There" Decent work there- looks like your Frankenstein 1377 has it beat, however. What hammer mods do you put in this one? Anyone ever hear of a pumper that only requires a few pumps to get 600+ fps? I think maybe one of the larger manufacturers should have gotten on this by now (but I guess not)... _________________ ` I'd say "I care." But I'd be lying. Canadian Airgun Supplier: http://www.scopesandammo.com/storefront   Posted: Tue Feb 10, 2026 9:57 am Old Lampy Member Joined: 23 Dec 2025 Posts: 39 AirGunEric wrote: Decent work there- looks like your Frankenstein 1377 has it beat, however. What hammer mods do you put in this one? The hammer is from a 2100, the spring is as long as I could fit with out coil bind. It seems to be a good set up as there is very little air leftover in the valve at 10 pumps. _________________ "Where ever you go... There you are." Buckaroo Banzai 1984   Posted: Tue Feb 10, 2026 10:19 am Old Lampy Member Joined: 23 Dec 2025 Posts: 39 AirGunEric wrote: Anyone ever hear of a pumper that only requires a few pumps to get 600+ fps? I think maybe one of the larger manufacturers should have gotten on this by now (but I guess not)... FX had this about a decade ago https://www.airgunsofarizona.com/precharged-pcp/fx-independence-.22/ Air gun companies seem to have focused all their energy on the PCP market for the last 10 or 15 years. I looked at Pumpers on Pyramyds web site and there isn't much there. mostly entry level stuff. I don't have anything against PCPs I just don't like the idea of having to pack a scuba tank or spend 10 minutes using a hand pump to fill the reservoir on my PCP. _________________ "Where ever you go... There you are." Buckaroo Banzai 1984   Posted: Fri Feb 13, 2026 1:55 am AirGunEric Site Admin Joined: 20 Jan 2007 Posts: 6929 Location: "Out There" Old Lampy wrote: I don't have anything against PCPs I just don't like the idea of having to pack a scuba tank or spend 10 minutes using a hand pump to fill the reservoir on my PCP. -Or maybe an Airforce Condor rifle and its tank- they weigh a ton all by themselves (i.e. like approaching the weight of a SCUBA tank). Absurd. _________________ ` I'd say "I care." But I'd be lying. Canadian Airgun Supplier: http://www.scopesandammo.com/storefront   Posted: Tue Feb 17, 2026 7:25 pm Old Lampy Member Joined: 23 Dec 2025 Posts: 39 I had this beast out today. I did a teardown and checked out the exhaust valve. I had a mod in mind that I wanted to try out, decreasing the internal volume of the exhaust valve. My thinking is that for the same number of pumps with the smaller volume I should get higher pressure. Higher pressure = more fps.... In my parts stash I had a check valve that was 3 times as long as the one that was in it, I found a shorter spring with lighter wire and put it back together. It seems to have worked, I'm seeing 630 fps at 6 pumps a gain of 80 fps. I'm going to spend some time tomorrow backing up these numbers and seeing if 8 and 10 pumps are worth the effort. _________________ "Where ever you go... There you are." Buckaroo Banzai 1984 One more project     Air Gun Home Forum Index » Rifles You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum All times are GMT - 5 Hours   Page 1 of 1   All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First  Select a forum Main Forums----------------AirGunHome Q&AGeneral Air Gun Questions and TopicsPicture GalleryTarget Shooting: Casual, Fun and CompetitionHunting, Pest Control, Varminting People/Events/Airgun Issue Discussion----------------Introduce YourselfThe BS TopicClubs/Events/Regional/Political Airgun Issues Maintenance, Modification and Reviews----------------RiflesPistolsAntique, Collector and Novelty AirgunsBB GunsPellets/AmmoOpticsAccessoriesAirgun Smithing Buy, Sell or Trade Forums----------------For SaleWant to Buy   Note: If you are seeing "Please enter your username and password to log in." Your browser cookies have been reset or you need to register to access the topic in question. Use the 'Register' button near the top left of this page. Click Here for AirGunHome.com Main Page Powered by phpBB © 2001-2004 phpBB Group Partial Styling Supplied by Vjacheslav Trushkin Themes Database.