Crosman Model-1300 Medalist II with .177 barrel
With thanks to Timothy.
He says:
Seeing room for improvement I made a few more modifications & am really pumped up with the results.
1rst … though using the 1377 rear cocker, the trigger could be improved further with a little attention to the contact points & reducing the spring by about 1 coil. It is still a little long but, butter smooth!2nd … better front sight by Blue Fork & fits the modern 13xx pistols, which meant shorting the tube by 7/32” to align the pivot pin holes & relieving the pump handle just a little to vent the compression chamber at full extension.
3rd … replaced my modified 1377 pump rod & cup with the correct 1300 medalist pump rod & cup + flat topped the 1377 valve to match. I’m using the old style 1377 check valve which reduces volume by a little & angled the exhaust for better flow. Lastly changed out the OEM TP for poly tubing. Results nearly 10% gain in fps (10 pumps was 340 with 14.3 CPHP from walmart & now 370fps).
curiosity got the best of me … (only did 1x but 15 pumps = 414fps with no residual air)
… the longer phase 2 1377 barrel hit 490fps with 7.9gr & 10 pumps
… installing my phase 1 1322 upper saw close to 15fps gain over the shorter barreli really like this pistol but NOT the original blow off valve!
When thinking about this I couldn’t find a lot of mod recommendations for the 1300 Medalist & hope this is of interest to others.
Mods made:
SSP .177 barrel shortened to 9 inches (10 was too long to my eye)
Barrel was married to an old style steel breech & port modded for a polly seal.
Magnet was removed from the probe & hollowed like the .22 probe.
Metal rear site was replaced with a plastic site modded (lowered) to get it to on at 30’ in my basement.Performance wise FPE is dead nuts with the .22 barrel
10.5 CPs - 8 pumps 411fps & 10 pumps 430fps
8.64 HNs - 8 pumps 447fps & 10 pumps 470fps