SMK TH78

 

So we have a new gun and I have to say I really like the stock. But of course though It has an identical action to the QB78, this one is brand new and I know its history from day one.

There was bit to much spring tension on the trigger making it sound, well frankly, crunchy so I slackened off the pressure and set the limit screw to reduce the trigger movement and it is much better for these adjustments. I have not yet adjusted the sear though. In due course I will probably put a thin washer either end of that spring, which should eliminate the crunchy feeling altogether.

Yesterday It was a lot cooler and I tried to do the pellet power testing. And after a few problems with the chrono lighting I got some results which I found pretty disappointing if I am honest, but to be fair part of this was probably the gas.Which was not lasting long and seemed not to be producing the sort of power it should be,

From my research these guns are set to between 6 – 8 ft lbs when they leave SMK and this seemed to be true, however they were nowhere near SMK’s quoted 550 fps no matter what pellet I used.

In fact from the sample pack of 19 pellets that I used, the Bisley magnums produce just over the legal limit of power and the rest were within the 6 – 8 ft lbs range. Bisley’s are not my favourite pellet, as they are made in Germany and I will not knowingly buy from EU countries at this time, so I wont be buying any and they wont get used. Bisley Magnums also give Julia’s little rifle its  maximum power which is well less than 11 ft lbs, but the grouping is nothing to be proud of. The staples will for me me the Crossman domed, Crossman premier ultra magnums, Air arms diabolo and air arms dilabolo heavy and also the Falcon accuracy. Plus I have a few Remington spikes to use up

I will be tuning this gun, I will probably get the tuning parts asap as they will keep and they could be a lot dearer in a years time,

I had to move the scope a bit as it was catching on the magazine so the scope needs zeroing in again. However  the new scope has now arrived and it is a very good scope for the money £35. I have  fitted the new scope to rifle as it is a better fit and allows more room for loading the pellet manually.  it just about scoped in now, but because it is so new I seem to be getting quite a few flyers. I am also not that sure if the gas is holding up as it should. It is reasonable today so should be OK but it is surprising how many shots it can take to zero in a scope. So it could now be a bit low on gas. Doing the pellet tests yesterday I must have put 20 odd shots through the rifle. and I have put at least that through it today as well so lets say it has had 40 to 45 shots from the gas so it must be getting low by now,

The scope that has come off this rifle has found it’s way onto the QB78 Though I can’t scope it in at the moment. Would not be much point in doing so anyway as I will be stripping it again soon and replacing the exhaust valve and block, plus the transfer port and the rest of the new parts I got for this rifle a while ago.

I have also ordered a tuning kit for the TH78, but I will not be fitting that just yet, It would almost certainly invalidate it’s guarantee if I tuned it.

I have as of 26th October fitted the Tuning kit. I wont detail it here because essentially it is the same procedure as for the QB78