HW 44 Fps Velocity Drop from 810 to 625 - Fixed by AOA

About four weeks ago I noticed a drop in the POI of my HW 44. At first I thought it might be a scope issue, but that checked out ok. I then chronied the velocity and found that it had dropped by about 200 ft./s. I checked to make sure the probe seal was not the problem and there was no blowback from the receiver. The weapon was still under warranty, so I gave AoA a call and they said to send it back. I sent it back and they fixed the issue. I know that others on this forum have had the same problem. Here is what AoA said the problem was and how they fixed it: 

Hi Charles,
I wanted to let you know that your HW44 has been repaired and will be shipping back to you. The hammer adjustment screw had backed out so we re adjusted it to get back to factory power and then secured the adjustment locking screw to ensure that it won't drop again. Your pistol should leave today and you will get tracking info when it does. Please let me know if you have any questions.

Thanks,
Shane
Airguns of Arizona
Service Department

I can’t thank AoA enough for the great service and quick turn around time. From the receipt of the pistol to repair, took less than a week. If your pistol has this problem and is still under warranty, I advise shipping it back to where you purchased it and have it fixed. If not, you may want to investigate the hammer spring to see if it has backed out. I have seen videos on YouTube that show how to adjust the hammer spring, so you should be able to fix the issue after viewing one of these. I have had this issue develop on other PCPs and after eliminating the “usual suspects”, it was always the hammer spring backing out. I kind of assumed that this was the issue but with the pistol being under warranty, I did not want to chance mucking it up. The HW44 is a complicated piece of German engineering and I love mine dearly. I have killed more tree rats with this weapon than any other. The trigger spring adjustment is probably one of the least complicated adjustments to make and you should be able to accomplish it without much trouble.

I hope this information is beneficial to anyone experiencing the same problem. I know there are other issues that can cause velocity drop (probe seal, etc.), but if you have checked all those and the problem still exist, you may want to look at this.



Charlie

 
  • Like
Reactions: cavedweller
image.1645552442.jpg


CPHP = Crosman Premier Hollow Point at 7.9 Gr

CPH =. Crosman Heavy Domed at 10.5 Gr
 
No mine is fine in that regard. That was one of the things I tested to see if I was losing any air at the breech seal. I put a tissue on top covering the receiver portion and did not get any motion. Has it had any impact on your velocity? You may want to look at some of the oversized breech seals from the UK. They claim one of these will cure popping and blowback.
 
Shot count: 15
Low: 858
Hi: 870
Avg: 864
Spread: 12
STD Dev: 3.2
865
865
865
865
863
865
865
865
865
861
870
865
858
858
863
New shot data for the HW 44. I’m amazed. I was getting 810 ft./s before the hammer went South. Now back from AoA I’m getting around 863. Not too shabby. It falls off the regulator at around shot 16. At the end of two magazines it is down around 845 with no appreciable affect on point of impact. But that’s OK. I’ll take the increase speed any day.
 
Shot count: 15
Low: 858
Hi: 870
Avg: 864
Spread: 12
STD Dev: 3.2
865
865
865
865
863
865
865
865
865
861
870
865
858
858
863
New shot data for the HW 44. I’m amazed. I was getting 810 ft./s before the hammer went South. Now back from AoA I’m getting around 863. Not too shabby. It falls off the regulator at around shot 16. At the end of two magazines it is down around 845 with no appreciable affect on point of impact. But that’s OK. I’ll take the increase speed any day.

That’s an mpressive shot string. Shane at AOA does put in time to communicate with and help out customers. I don’t know where he finds the time considering how large their base is. 
 
Just got back and with the H&N cuda match (177) I am only getting 720 average over a 10 shot string. Guess I better learn how to adjust hammer spring…I bought the pistol used months ago.

Tony P
I'm getting the same FPS with my HW44 with 8.44gn pellets. I also bought mine used a few months ago. I assume you got yours fixed? What was the issue?