i'll take a stab at this. yes pumpers can be made competitive. i would start by reducing valve volume so you can get to pressure with less pumps. either use an adjustable piston or shim the pump cup to reduce headspace. a note on breeches is in order here. it's been awhile since i've seen a breech that was actually radiused on the bottom for the pumper tube. most after market breeches are machined to fit the 2240 size tube which is slightly larger than the 1377 tube. i have a breech made for the 13xx guns, but got it awhile back. i've seen people put everything from glass bedding to that metal putty, jb weld etc. under the edges to help stabilize the breech. the biggest thing with the 13xx guns is keeping everything from wiggling about. a good metal front barrel band would absolutely be needed. good solid pins would also be a must. even a second band close to the breech would be beneficial to the stabilization effort. if using a crosman breech, an extra screw to hold down the barrel would be a good idea. the p-rod trigger swap and a lw barrel would round out the package. i have one that has 10 meter accuracy, but the longer the shooting sessions can start screwing with accuracy from fatigue. probably won't be as critical on field target as there is time between lanes. but if your heart gets pumping it will bounce in your hand. accuracy is possible with money and work, practicality is a different subject that you didn't want to get into..so i won't..lolhave funpeacekj
I think starting out with a custom shop 1300kt with the lw barrel... Then kj hobbit exactly on the head.... Stuff the valve to build power with less pumps, adjustable pump arm with the stock pumpcup and newer valve profile, Prod trigger.... Nice optic and have fun.....
Could you ... YESShould you .. NOAs to the WHY for ... CONSISTENCY shot to shot.Pneumatic guns create HEAT when pumped up, more sequential shots done warmer things get and velocity slows down somewhat as you go.Also User fatigue is VERY REAL and pumping a gun up and expecting you can be relaxed enough to shoot FT accuracy IMO just ain't going to happen. As a competitive FT shooter in Both Rifle & Pistol disciplines I offer my opinion with some real world experience. Have fun tho what ever you do
there are two thoughts on valve volume.... you can either go with MAXIMUM power which would call for an increase in valve volume and corresponding number of pumps... OR you can go for maximum efficiency/pump which calls for a reduced valve volume..... in the 13xx series the cross over seems to be about 12-15 pumps..... if you never plan on pumping more then that you will get better results by stuffing the valve..... this allows you to build pressure faster inside the valve giving you better speeds with less pumping but it will limit your MAX power with its reduced volume.... if you want maximum power you would want to increase the volume in the valve... it requires more pumps to get the pressure built but with more air volume you can get more power.....pretty simple really...