Canadian Airgun Forum

Been keeping busy with various things this winter, 2 progects on the go in my airgun collection. Here is the first as its the closest to completion.

A custom 2250b PCP Pistol build

Before the flood of replies about +500fps and rpal, it will be tuned down to sub 500fps by valve work/hammer spring work, I havent recieved the valve in the mail yet so I can't test it. It will be running on HPA regulated at 800psi to start and I will be tuning further to adjust shot count and velocity once I get the last few parts in.

sorry for the pics, iphone cant take a decent pic indoors for some reason.

Here is the list so far, I'm still looking for a AR/M style grip that would look good on this setup and a barrel band to match.

Purchased:
Blueforks Designs AR15 Grip Frame
2250b Tube Powder Coated "Gold"
Brass Left Handed Breech
Brass Breech Cap
Discovery Valve
2289 Hammer Spring
Brass Bulk Fill Tube Cap W/Male Foster
Stock 2240 Barrel Band

I've made:
10" Crosman .22 Barrel (cut down 14" barrel re-crowned)
Brass Back Cap
Brass Bolt w/ Extended Probe
Brass & Stainless Handle
Poly Transfer Port Tube
Brass 1.75" Hex Muzzle Brake

Pics:





More to come once completed and watch for the other project to be posted in the next few weeks!!!
GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911

"Th Man with the Golden Gun"
Jk Jeff! Looks great! I found two wood pistol grips for the BlueFork if you are still looking!

http://www.davidtubb.com/t2k-rh-wood-grip-walnut
http://www.ironwooddesigns.com

_________________
-Rick

Brocock Concept .22
3 Crosman MK 1 pistol .22

LOL thanks

I did run across those sites in my searches as well, I thinking about the walnut grip and finishing it to suit the pistol, and or the black target grip...

GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911

After I got tired of looking at this gem today I swapped the BFD frame out for a stock 2240 and installed the discovery valve and proceeded to fill with 850psi HPA..... or so I thought .... with the brass brake attached, I cannot attach the remote line to fill!!, so my measurements were off on the barrel length 10.25" was too short. For testing purposes I removed the brake and went ahead with it. for the first 5 shots I stayed tethered to the 43ci bottle for consistancy and shot an average of 482.6fps with a 14.3gr Crosman HP.

At this point I knew I was wasting a lot of air per shot (very loud) which I fully expected.

I then decided to see how many shots per fill.... lol yeah another sign of gas wasted, 1 shot at 485fps, next shot at 345fps and the pellet did not move on the third... remember the valve is an unmodified discovery valve designed for pcp ~2000psi and hammer spring is an unmodified 2289 spring.

Also between the valve and bulk fill endcap there really isn't much "open space" in the 2250 tube for air capacity

That was it for today, I need to shorten another barrel I'm thinking 13" or so for clearance of the remote line, get a new baseline, make and install the RVA and continue testing.

GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911

Jeff, I can make you a flat bottomed brake if you like. I think I have it, a similar sample in aluminum, at home and can send you a pic of it. I know I have apiece of 1 1/2" brass that would work. I should have offered you a brake for the barrel work I did also! Dummy me!

_________________
-Rick

Brocock Concept .22
3 Crosman MK 1 pistol .22

Instead of a flat bottomed brake how about a 1 1/8" ball end mill. At least that way you can keep a fuller look of the brake. JMO

Something like this heavy bbl 2040 for end cap and powerlet removal.

_________________
May the cry of the pack be with you upon your hunt

Whitewolf

thanks for the ideas guys, i appreciate the offer rrdstarr no big deal, i have a plan for that barrel, lol i just need to get a new tap to finish it nicely.....

im going to stay with a longer barrel for now for this build.

GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911

here is another update on this build,

I have installed a standard mil-spec buffer tube with a Magpul CTR Carbine Mil-spec stock, the adaptor from the 2250 tube to the buffer tube was made by rrdstarr (Rick) again excellent quality!!!. For the pistol grip I installed a Magpul MOE-K Grip on the Bluefork designs trigger group.

http://ctcsupplies.ca/collections/stock ... k-mil-spec
http://ctcsupplies.ca/collections/gun-p ... moe-k-grip

I am still debating on what barrel length I'm swapping to, currently its throwing 14.3gr pellets at 483fps with a 10" barrel, I may go to a 14"/18" for the carbine look, which will likely require some tuning to keep the velocity down below 500fps.

I also have a sling mount (buffer tube style) but it didn't ship with the castle nut, so its on its way in the mail...






more to come!!!
GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911

The MagPul stock and adapter look really nice Jeff!

_________________
-Rick

Brocock Concept .22
3 Crosman MK 1 pistol .22

_________________
'''''''''''''''''' - _GUNZLAW _- '''''''''''''''''''
-----------------------------------
- si vis pacem , parabellum .

thanks guys,

well had some time with my son and he wanted to work on the airguns

so we worked a different barrel for this project.

I picked up an older 18" Crosman barrel, walked to the lathe and my son said "can I do the work?", my response, "grab your glasses!"

I asked how long should it be, lol he says "ohh about here", turns out he was close to where I wanted it, marked it at 16.25", changed to the parting tool and gave a quick refresher on functions. with the power off to start he lined up to make the cut, turned the power on and away we went.....I had to get him to speed up the in-feed just a bit but it went pretty good!!!

Next I explained the crown and he seemed to grasp the idea pretty quick. so a quick change to the facing tool (side note I showed him the old 4-side bit holder, he was glad I had the QCTP ) and cleaned up the muzzle. next we cheated and chucked up a 60* countersink bit in the tail stock to make the crown, cutting until there was a solid 1/8" land for the crown. he changed back to the facing tool and re-faced the muzzle until the land was ~1/16".

I took over with the sandpaper to polish, starting at 800grit ending at 1500grit.

he spent about 20min with q-tips patches and a jag, cleaning the barrel (from the breech end) no snags

we reassembled the carbine and here is the result, with the magpul stock the LOP is 12" at the shortest 15" at the longest




One thing I don't think I mentioned is the stock adaptor Rick (rrdstar) made has a rva built into it, sort of hard the see here but the hammer spring is very accurately retained by the stock adaptor which is threaded 5/16-24, with the use of a set-screw/grub screw, once the tune is set the buffer tube can be installed and no worries to be had of it changing!!!


we will hopefully get to some tuning done on this next weekend, but for now, the chrony results are promising

GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911

Looking really nice Jeff!

_________________
-Rick

Brocock Concept .22
3 Crosman MK 1 pistol .22

ok here is the first tuning results

this is the string I left off at this morning.
850psi hpa using 14.3gr Crosman pellets. The hammer spring is a 2289 spring, I had to clip 5.75 coils to get it to this point (4.75 just to get it non rpal)
this is also without the rva adjustment screw, my theory is, I can add tension easier than remove it so start low and bring it up

1- 453.9
2- 464.9
3- 466.5
4- 465.9
5- 460.6
6- 450.3
7- 407.2


not exactly a great number of shots but in fairness there is not a volume to work with between the bigger valve and the bulk adaptor.

More to come
GT

_________________
QB.30 PCP w/ Leapers Bug Buster 4x32AO Mil-Dot
QB78D .22 w/ Leapers 3-9x40AO Mil-Dot
QB78 .22 Custom HFT Stock w/ Leapers 3-9x40AO Mil-Dot
Crosman 1100
Crosman 2240
Custom 2050
Brass M2250
Tanfoglio 1911