TM 1000 reg issues I think
I recently had to replace the o-rings in my action due to a leak. I had not shot the gun in a while and it was not holding air. It is now holding fine but I think something may be going on with the regulator. I seem to be getting around 40 shots at 17 fpe before it falls off the reg. That is at about 140 bar. I am also getting some flyers that are not explained by poor shooing fundamentals. Yesterday I replaced the hammer spring and polished the hammer and am getting more power now but still falling off sooner than I think it should. BTW it is .177 and I shoot A 10.3 at around 916 fps. Before replacing the spring I could not get more than 884. The spring was getting pretty weak I think. I had not shot the gun for a year but am shooting it again this season. Does it sound like the reg may be out of adjustment or just needs replacing? sI am hoping for specific guidance from those who shoot this gun. Generic theories may not be helpful.
At 884 fps original setting, you had 17.87 fpe which is what the rifle would have been set at give or take .
Now at 916 fps it is shooting at 19.2 fpe. If the gauge is somewhat accurate and your check is showing the rifle dropping off the reg at 140 bar then it is wasting air. The original setting would have been around 110 bar +/- for the HV TM 1000.
Could I suggest:
1. Reduce the hammer spring pre-load back to give 880 fps with your new spring, and check the number of shots again.
2. If the rifle comes off the reg at 140 bar: either get the instruction sheet and a set of O rings for servicing the reg from Martin at RAW and do the service which is simple but really requires an accurate gauge for accurate setting (WIKA @ about $30) ; or send it to Martin for servicing and re-setting.
In any case for most accurate shooting over ranges past 30 yards and in any wind, the 10.3 gr pellet will do its best at 880 fps or less. 17 fpe is achieved at 862 fps and that is a good power for that pellet for the HV benchrest game shot outdoors.
An even better pellet is the 13.43 gr JSB pushed to near 20 fpe for competition and long range accuracy ( 20 fpe for this pellet is 818 fps and the BC is higher more than or at least making up for the lesser comparative velocities).
All the above is with regard to my TM 1000 and experiments with Labradar and SM flight video.
Edit added: At 916 fps you will get spiralling fliers wit the 10.3 gr pellet especially in wind.
Kind regards, Harry. I hope this is of some help L.
Not sure why you are cutting any springs. You should be able to adjust the hammer spring in order to raise or lower the velocity. If you send anything back to Martin, just remove the stock and send the rest. If you do send the whole works, ask Martin to notch out the stock , so that you can adjust the velocity with the hammer spring without taking the works out of the stock. Much easier.
I just picked mine up the other day at Minor Hill. I think that the hammer spring may have gotten a little weaker over the last 3 years. Martin went through the whole rifle and replaced all the o-rings, adjusted the trigger a little lighter and checked the regulator. It's set at 860 fps now and dead on at 55 yards with JSB 10.3's. I'm now getting well over 80 shots with a fill of 3,000 psi and a difference + or - of 5 fps all the way to 8o shots. I got tried of writing at that point. When I first got the rifle, it was shooting at 910 fps and pretty accurate and I could shoot a 60 shot match easily. I have shot it down to 845 fps and it was accurate, but I think it will fight the wind better at 860 fps. From the bench, it will easily group 5-10 shots in a 1" KZ at 55 yards. I can't do it from any position. Wish that I could.
Hope this helps,
I had to cut the new spring I got from martin. I am sure martin cuts them to get what he wants since the cut end was not flattened square. It has many more coils than the old one. Even backed out as far as the stock would allow it was doing 915 fps with AA 10.3 and gulping air. I now have it shooting 865 with the adjustment about half way out. If I screw it down a few turns it hits 880 with more turns to go.. I am liking the shot count at 865. BTW, my old spring was indeed weakened. turned all the way in it was at 884 but no more to go. I could have lived with 884 but decided to replace the spring. Some of my lower shot count is due to the old style barrel which is shorter that some I have seen.
I rebuilt the gun myself from an O ring kit from martin. It wasn't rocket science. the only thing I did not do is rework the reg.. I may send the reg back to have martin. re and do it but I am not sure it needs it. the gun is now very consistent down to at least half way between the 150 and 100 bar mark but my gauge is not