Here fir 1322 mods

[Tack Driver 10]

Ran the gun over the chrony after modification.
2100 hammer spring, 90 duro valve seal, pin intake port.

Before mod:
With 14.3 CPHPs
05 pumps= 440 FPS  06.15 FPE
07 pumps= 515 FPS  08.42 FPE
10 pumps= 594 FPS  11.20 FPE
12 pumps= 624 FPS  12.36 FPE
15 pumps= 667 FPS  14.12 FPE

After mod:
With 14.3 CPHPs
05 pumps= 457 FPS  06.63 FPE
07 pumps= 537 FPS  09.15 FPE
10 pumps= 625 FPS  12.40 FPE
12 pumps= 649 FPS  13.21 FPE
15 pumps= 682 FPS  14.76 FPE

I can see by the velocity response that the valve could use more volume.
It's optimized at 10 pumps and tails off past that point.

[Tack Driver 10]

Decided to try a .177 cal barrel on this gun.
Replaced the .22 cal 20" barrel with a .177 cal 18" barrel.

With 14.3 CPHPs (.22 cal 20" barrel)
05 pumps= 457 FPS  06.63 FPE
07 pumps= 537 FPS  09.15 FPE
10 pumps= 625 FPS  12.40 FPE
12 pumps= 649 FPS  13.21 FPE
15 pumps= 682 FPS  14.76 FPE

With 7.9 CPHPs (.177 cal 18" barrel)
05 pumps= 552 FPS  05.34 FPE
07 pumps= 634 FPS  07.05 FPE
10 pumps= 724 FPS  09.19 FPE
12 pumps= 752 FPS  09.92 FPE
15 pumps= 800 FPS  11.22 FPE

With 10.65 grain Barracuda Match pellet
10 pumps=655 FPS  10.14 FPE

[Hoosier Daddy]

I bet your groups improved... no?

[Tack Driver 10]

I bet your groups improved... no?

I built this test gun as an pump cup fueled experiment and haven't sighted it in.

[anti-squirrel]

An observation from my own 1377/1322 efforts; it is far more cost-effective to get a 1300KT (with the LW barrel if you have the funds) as a starting point. 

[DHunter]

An observation from my own 1377/1322 efforts; it is far more cost-effective to get a 1300KT (with the LW barrel if you have the funds) as a starting point.

What's the deal with the LW barrel?  The Crosman one seems to be super accurate as it is.  I only have the stock pistol so far, and it's as accurate as I can imagine it being with my hand-holding it with no shoulder stock or scope; but I get the impression from what others write about theirs with the stock and steel breech and scope that they are super accurate.

[DHunter]

An observation from my own 1377/1322 efforts; it is far more cost-effective to get a 1300KT (with the LW barrel if you have the funds) as a starting point.

What's the deal with the LW barrel?  The Crosman one seems to be super accurate as it is.  I only have the stock pistol so far, and it's as accurate as I can imagine it being with my hand-holding it with no shoulder stock or scope; but I get the impression from what others write about theirs with the stock and steel breech and scope that they are super accurate.

I'll add some more to that.  I don't have enough posts yet to be allowed to post links, but go to YouTube and put "Benjamin Field & Target Regulated Marauder .22 cal" in the search box, by shooter1721, posted on Aug 12, 2017.  He shot a Benjamin Marauder .22 with a Crosman barrel, a 3/8" group at 55 yards.

[DHunter]

bump

An observation from my own 1377/1322 efforts; it is far more cost-effective to get a 1300KT (with the LW barrel if you have the funds) as a starting point.

What's the deal with the LW barrel?  The Crosman one seems to be super accurate as it is.  I only have the stock pistol so far, and it's as accurate as I can imagine it being with my hand-holding it with no shoulder stock or scope; but I get the impression from what others write about theirs with the stock and steel breech and scope that they are super accurate.

I'll add some more to that.  I don't have enough posts yet to be allowed to post links, but go to YouTube and put "Benjamin Field & Target Regulated Marauder .22 cal" in the search box, by shooter1721, posted on Aug 12, 2017.  He shot a Benjamin Marauder .22 with a Crosman barrel, a 3/8" group at 55 yards.