OK, this will be a little brain dump on this rifle because I'm trying to learn it and the ins-and-outs of FT (specifically WFTF division).
I picked up a used Air Arms s400 mpr this past winter and I'm just about to the point where I can say that I know what its capabilities are. This gun started out as a 5.1 fpe sporter manufactured in 2005. It has had several owners and along the way has been pretty extensively modified. It has a longer air tube (the original was included) and is now regulated. I have to assume that it was ported or opened up along the way.
Using the transfer port restrictor I can get a useful range of 755 fps (10.9 fpe) up to 877 fps (14.8) with H&N FTT pellets. I am getting 90 shots averaging 11.8 fpe with an extreme spread of 16 fps from a 200 bar fill. This was with the transfer port opened about 1/2 turn from being all the way in. The max velocity is reached about 4 full turns out. I know using the TP to limit velocity is not optimal, but I don't have much interest in opening this old girl up to mess with the hammer spring or regulator right now. I'm pretty happy with this tune. The gun came shooting pretty "hot" and I never was able to get it group well shooting that way. I think this gun is happiest at the 12 fpe level.
In my backyard bench testing I have it zero'd at 20 and 40 yards. I just read the Building a dope card for FT thread and will be playing with the mil grid target linked from it to see how I like it across the range of distances.
The gun came with a gigantic UTG scope and wheel which I'm not using. More out of convenience than anything else, I put on an Athlon 6-24x50 scope on it. I bought that scope used a while back and never really loved the reticle. It's pretty thick at 24x. However, I just tested a parallax wheel that came with a Discovery scope on the Athlon and found that it fits so that pretty much seals the deal in keeping the Athlon on her.
The gun arrived with an insanely light trigger. It was way too light for me (especially when shooting in the winter when it's hard to feel your fingers). I now have it set more firmly and in such a way that the trigger returns to "normal" when I get to the 2nd stage and release it.
So far I have only had to replace the pellet probe seal (inner barrel) and grind down the muzzle brake some more so it clears the end of the air tube better. At some point I may look to replace the muzzle brake with a Rowan air stripper. I am still curious to see if that could improve accuracy at higher velocities.
Now that I feel like I know the gun fairly well, I'll be getting off the bench, adding the hamster thingy and remembering how poorly I shoot when I am actually supporting the rifle myself... ;-)
Begin Pic Dump
68 yard target
Top row 40 yards, 40 yards, 20 yards
Bottom row 20 yards, 20 yards, 50 yards (1.25 inch drop / 3/4 mil)
I picked up a used Air Arms s400 mpr this past winter and I'm just about to the point where I can say that I know what its capabilities are. This gun started out as a 5.1 fpe sporter manufactured in 2005. It has had several owners and along the way has been pretty extensively modified. It has a longer air tube (the original was included) and is now regulated. I have to assume that it was ported or opened up along the way.
Using the transfer port restrictor I can get a useful range of 755 fps (10.9 fpe) up to 877 fps (14.8) with H&N FTT pellets. I am getting 90 shots averaging 11.8 fpe with an extreme spread of 16 fps from a 200 bar fill. This was with the transfer port opened about 1/2 turn from being all the way in. The max velocity is reached about 4 full turns out. I know using the TP to limit velocity is not optimal, but I don't have much interest in opening this old girl up to mess with the hammer spring or regulator right now. I'm pretty happy with this tune. The gun came shooting pretty "hot" and I never was able to get it group well shooting that way. I think this gun is happiest at the 12 fpe level.
In my backyard bench testing I have it zero'd at 20 and 40 yards. I just read the Building a dope card for FT thread and will be playing with the mil grid target linked from it to see how I like it across the range of distances.
The gun came with a gigantic UTG scope and wheel which I'm not using. More out of convenience than anything else, I put on an Athlon 6-24x50 scope on it. I bought that scope used a while back and never really loved the reticle. It's pretty thick at 24x. However, I just tested a parallax wheel that came with a Discovery scope on the Athlon and found that it fits so that pretty much seals the deal in keeping the Athlon on her.
The gun arrived with an insanely light trigger. It was way too light for me (especially when shooting in the winter when it's hard to feel your fingers). I now have it set more firmly and in such a way that the trigger returns to "normal" when I get to the 2nd stage and release it.
So far I have only had to replace the pellet probe seal (inner barrel) and grind down the muzzle brake some more so it clears the end of the air tube better. At some point I may look to replace the muzzle brake with a Rowan air stripper. I am still curious to see if that could improve accuracy at higher velocities.
Now that I feel like I know the gun fairly well, I'll be getting off the bench, adding the hamster thingy and remembering how poorly I shoot when I am actually supporting the rifle myself... ;-)
Begin Pic Dump
68 yard target
Top row 40 yards, 40 yards, 20 yards
Bottom row 20 yards, 20 yards, 50 yards (1.25 inch drop / 3/4 mil)
