Tuned .22 SMK XS 78

[Brutuz]

I've owned and tuned a .177 QB78 deluxe  which I've sold recently and bought a standard .22 SMK XS78.

Before selling the QB I switched the stock and triggergroup. I'm not a fan of the truglo sights, they are good but don't like the looks, so I din't swich those.

Started tuning the .22 according to the CdT method the day I received it.

I get abt 32 upto 35 good shots depending on the rate of fire.

Polished the inside of the hammerunit last night. Read people using emmery cloth, didn't have that so got some from Gmac together with an order of brass parts.

Turns out it's sandingpaper on a linnen back. Strange it's called emmery cloth, very confusing for Dutch people LOL.

So last night after polishing the inside of the hammer unit I preloaded the hammerspring with one shim instead of the 0.25" I used before and the results were the same as before the polishing, which is quite an improvement. Qurious as I am I preloaded the hammerspring to 0.25" again after shot 7 and notice no improvement, so I took them out again after shot 14 to see performance is good without them and it results in a flatter curve. No pausing beteween shoots. Never thought polishing the inside of the hammerunit would have such a positive effect.

                                                                                                                                                                                                                                                                                                                                     

SHOT		FPS	Rem.
1		677	first after reass. & 2 new powerl.
2		701	1 shim
3		701	1 shim
4		703	1 shim
5		698	1 shim
6		699	1 shim
7		701	1 shim
8		703	preloaded .25"
9		701	preloaded .25"
10		692	preloaded .25"
11		696	preloaded .25"
12		700	preloaded .25"
13		695	preloaded .25"
14		693	preloaded .25"
15		695	1 shim again
16		696	1 shim again
17		700	1 shim again
18		698	1 shim again
19		696	1 shim again
20		687	1 shim again

Since I'm very pleased with this rifle I ordered some brass parts from Gmac (UK)

Here's how it looks now.

MuzzleBrakes like in the pic are legal in the Netherlands.

If the last 2 pics are inappropriate a moderator may remove them together with this line and the statement above this line.

If you'd like to see some vids please check these I made

Take I

Take II

Take III

Take IV

Take V (under construction)

[lastmanout]

Beautiful job on the brass metalwork. Nice tune-up.

[Brutuz]

lastmanout - 12/16/2009  3:59 PM  Beautiful job on the brass metalwork. Nice tune-up.

Thanks

Made the last vid this afternoon:

http://www.youtube.com/watch?v=A_4pmh3duys

[Jaymo]

It's called emery cloth because it's emery abrasive on a cloth backing. Now, why is crocus cloth called crocus?

[dk1677]

Very nice work!

[Brutuz]

Jaymo - 12/17/2009  3:32 AM  It's called emery cloth because it's emery abrasive on a cloth backing. Now, why is crocus cloth called crocus?

Emery isn't a common English word overhere, hence the confusion thinking it was something special which it isn't.

On the crocus remark I would apreciate a bit of understanding for foreigners more than talking us down like that Jeremy.

Just read some of your earlier posts and you look like a cool guy

[Brutuz]

Check this

[Brutuz]

Grouping wasn't bad, 2 five shot groups @ 10 meter:

[Jaymo]

I wasn't talking down to you, Brutuz. I apologize if it came across that way. That was not my intention. I actually wonder why crocus cloth abrasive is called that. I don't know if crocus means something in Dutch that it doesn't mean in English, but crocus cloth is an actual abrasive/polishing cloth here in the USA.

[Jaymo]

According to about.com, crocus cloth is an iron oxide coated abrasive cloth, used as a polishing agent after most of the work has been done with aluminum oxide or emery. Basically granular rouge. Sure makes more sense than coating cloth with a crocus flower.

It says that emery is a granular form of impure corundum.

[Brutuz]

Overhere we only know the crocus as being a flower/plant, hence another confusion on my part. Thanks for explaining it.

[Brutuz]

Did the extended probe mod and boy am I sorry I did.

Gain in fps: ok

Uses more CO2: can live with that

Loading pellets: big dissapointment - they tumble/tilt now

Seems to me the only way you can load a pellet is whith the barrel pointed to the floor.

Here's a vid I made

[Jaymo]

Sorry the bolt probe mod didn't work out for you. i may not do that to mine.

Yeah, when I did a Google search for crocus, I came up with  a European flower, also. I thought, "Surely abrasive cloth isn't made of THIS." ;`)

In retrospect, I can see why it's not called rust cloth. Nobody would buy it. Why they don't just call it rouge paper, I don't know.

[Brutuz]

Tested a few other pellets today, it seems only these H&N hollowpoints and the smaller pellets tilt, others loaded smoother.

Still think the hollow probe loads easier, so if you're looking for extra fps the extended probe is last on my list.

[Brutuz]

Thanks to a member of ukchineseairgunforum.myfreeforum.org it's got an extended hollow probe now :-)