1322 mods completed - is my power low?

[Luthier Vandros]

Hi, all.

Hope this note finds you and yours well.  I've just finished a round of mods to my new 1322, which include:

1.Crosman 14" barrel w/5" TKO Moderator
2. Alchemy FT P/V & ported xfer port boss (barrel not port matched, however)
3. Crosman steel breech
4. Maverick steel barrel band/rear tube/breech link
5. extended probe

I deburred the main tube and other bits, cleaned and assembled parts using a little secret sauce and silicone grease where applicable.  No perceptible leaks that I can find.  Barrel and breech are properly seated.  Exhaust port on valve was centered.

I am seeing 550 fps @ 20 umps using 14.66 grain H&N Field Target Trophy pellets.  Is this about right?

[CraigH]

Altitude dependent to a fair degree - also did not notice the number of pumps - any air retained?

If near sea level, and barrel opened to the rest of the air path, and 10 pumps, and no air retained, may be a bit low.   As is, close.

[Luthier Vandros]

Hi, at sea level - 20 pumps with no retained air.  To be fair I believe the alchemy website mentioned about 100fps gain at 20 pumps, so its fairly close to that.

[crossliner]

This is the reason why I no longer use my 13xx--mine is just for display 

Well, mine does not have power mods, but I already got bored pumping it.

20 pumps for 1 bang, did you say? 

That is about the same number of pumps (even less) with my hand pump when I refill my 2260 and hybrid PROD PCP's.

[Luthier Vandros]

This is the reason why I [/youtube] use my 13xx--mine is just for display 

Well, mine does not have power mods, but I already got bored pumping it.

20 pumps for 1 bang, did you say? 

That is about the same number of pumps (even less) with my hand pump when I refill my 2260 and hybrid PROD PCP's.

Thanks for the dazzling contribution to this discussion.

[crossliner]

Well, I am just stating a fact if you are thinking about another build.

Like you, I have spent hundreds of $ on my 13xx (we have the same laminate colors in the GTA), then it made me realize I actually prefer my low power and low air load PCP's, hence I no longer use mine.

[Luthier Vandros]

All good, my man. I've got an older RWS springer as my primary, but it's in the midst of getting some much needed maintenance. This build turned into something else as I have been waiting on the RWS to get back lol.

[CraigH]

Here is data from my 1322C with FTP, 18" barrel, and SSS (Short Stiff Spring) of 0.045 wire 1.5" long.   Altitude is 5835 feet above seal level.

Pumps   Average FPS    ES         SD        Sea Level Equivalent
6              436.6           1.54     1.00        471.5
10             514.6          5.23     2.44        555.8
15             562.7          1.49      1.00        607.8
20             588.7           3.63     2.00        635.8

EDIT:    Also has Mellon flow-through bolt/probe.

[Luthier Vandros]

I feel like I'm right where I should be with it after seeing that, Craig. Maybe a little short, but I'm running a 12" barrel.

[CraigH]

Thought you said 14" barrel.   

[Luthier Vandros]

Whoops. Glad one of us is reading the message lol!  It is 12" indeed.

[nervoustrigger]

Your results are about right.  I looked back at my records on a 2289 I tinkered with several years ago.

https://www.gatewaytoairguns.org/GTA/index.php?topic=44342

The 2289 is (was) a 1322 with a barrel 2" longer so that makes it an identical length as yours.  On mine I did strictly simple DIY mods to shim the pump cup and stiffen the plastic OEM piston.  The result was 8.9fpe at 10 pumps vs your 9.8fpe on 20 pumps.  Yours may be producing a bit less than expected but I bet you are getting very little benefit from the additional 10 pumps other than Popeye forearms and accelerated wear on the pump linkage.  What is yours doing with 10 pumps?

[Luthier Vandros]

Ty for responding. The resistance is very light even at 20 pumps. Very smooth action. I'll chronograph at 10 pumps and will respond back. I think it was around 500fps IIRC.

[Luthier Vandros]

10 pumps @ 485 ft./s
20 pumps @ 550 ft./s
30 pumps gave me 585 ft./s

All with no air left in reserve.

[1377x]

i think 30 pumps is overkill imo. take it from me when the bug bit i did all kinds of mods which lead to increasing hammer springs pumping 50x but iirc i was pushing 18gr pellets over 600fps 30 pumps 14.5" .22 barrel. luckily i had a crosman repair shop here now retired. i pretty much quit modding crosmans after he retired parts were more expensive had to order from crosman no more discounts. lol not my cup of tea but when the shop was open i was able to help people out with hard to get parts like the pellet loader for the 1389 brass valves and original flat top pistons from crosman. that reminds me i have to find my crosman parts and get rid of them they will be of use to someone other than myself they are collecting dust somewhere.