FX Question about slug power kit in M3

DBlue

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Dec 14, 2022
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I ordered a 1/16 twist slug liner with a carbon fiber sleeve and the slug power kit. I’m trying to get better accuracy with Nielsen 33.6 grain slugs…the stock liner is just not accurate enough with them. I’m not trying to get any crazy speed , I’m just after better accuracy.
My question is , should I install the slug kit or try it with just the different liner? I’ve read several posts about not needing the slug power kit. I’m thinking just install the new probe with the liner…????
 
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Need more info. Mainly barrel length. But I will say that I have three M3 sluggers. A .25 compact, .22 compact and a .25 600mm. No power adders or funky slug stuff. I won’t deny I tested that stuff, but it’s all in a parts drawer now. And good luck with that 1:16. Mine is also now in a tube of other unused metal tubes. I tried a 500mm one. Maybe in 6 or 700mm is where they shine. Maybe.
 
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You can try the slug liner and it won’t cost too much. I would shoot the STX liner that came with the gun and play with tunes before I made the jump to a the 1/16 twist liner. Slugs and liners are odd things.
I have a 600mm M3 that I could not get 27.5 slugs to group with the STX Liner by all that is said it should have done a great job. Put a slug liner in and it shoots great. Got nothing. Just have to play around and see what works.
My experience with CF liners is a big fat yawn. In fact the last one cost me a liner in my Maverick 600mm 22. Ran out of O rings for the liner so got a CF liner and put it on. Fit was not optimal so epoxied it in making sure that I rotated and slid it back and forth to get he epoxy as even as possible. Shot like doo doo no matter the tune.
Try your barrel without bonding the liner to the sleeve before bonding it. I didn’t and wished I had.
I had similar results with my M3 600mm 22. I wont be doing that again.
 
Thanks for the replies.....Got the new liner etc. this evening. I installed the liner and carbon fiber sleeve, did not bond it, there was a red mark on the end of the liner and I installed it at 12.00 position. I did install the new pin probe but didn't install the hammer parts and spring as I wanted to try it without it. I used my same tune I had with the stock liner, shot it through the chronograph and it's shooting the 25 cal. 33.6 Nielsen slugs at 985 fps. with the second reg at 120 bar, I deleted the first reg awhile back , it's a 700 mm. liner. It was almost dark by the time I got it back together, I set up a target with a light at 50 yards on my range, took 5 shots and dialed in the scope. I then shot two mags. 50 shots at a 1" target dot......here's a pic of the target I shot with it. .....this new liner with the new probe definitely made a difference with these slugs...:)

IMG_6440.jpg
 
I hate you 700mm guys. Speed comes so easily.😉

Just coasting along at 985 at 120b. Hopefully it holds up at distance. That would be great.
lol…..I’ll be shooting it more tomorrow for sure to see if that’s a fluke group or not. I’m also going to shoot at 100 yds., that will tell the real difference……with the stock liner it was all over the place at 100 yds. with these slugs. The crazy thing is, the stock liner is super accurate with JSB 33.95 mk2 pellets but just will not shoot these slugs nowhere near what I call accurate……
 
Looks like you already have this sorted, but for future reference the slug kit hammer weight is way too heavy. For most people using normal-high reg settings the hammer weight is almost double what you actually need. I am running 150-155Bar on my Impact and only have a Huma hammer spring and slightly heavier hammer weight. The FX tungsten weight is more for people running like 170-190Bar.
 
Looks like you already have this sorted, but for future reference the slug kit hammer weight is way too heavy. For most people using normal-high reg settings the hammer weight is almost double what you actually need. I am running 150-155Bar on my Impact and only have a Huma hammer spring and slightly heavier hammer weight. The FX tungsten weight is more for people running like 170-190Bar.
Thanks for the info…..there must be different slug kits they are selling, this kit I got has Two small spacers that are put on the factory spring guide that stiffens the hammer spring and add a little extra weight along with a lighter valve spring and the adjustable pin probe, it didn’t have a new hammer weight. I only installed the new probe from the kit.

IMG_6441.jpeg
 
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Thanks for the info…..there must be different slug kits they are selling, this kit I got has Two small spacers that are put on the factory spring guide that stiffens the hammer spring and add a little extra weight along with a lighter valve spring and the adjustable pin probe, it didn’t have a new hammer weight. I only installed the new probe from the kit.

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There has been several renditions of the slug kits. Some dont have the tungsten weight, some have steel weights etc.
 
There has been several renditions of the slug kits. Some dont have the tungsten weight, some have steel weights etc.
That's what I thought as this kit didn't have a tungsten weight. I wasn't looking to get the max speed, I just wanted to get the slugs shooting accurate as the stock liner just would not shoot them accurate enough for me. The tune I had with the stock liner, I was getting average 960 fps after installing the new probe with the new liner I picked up 25 fps....I'm shooting it now with the exact same settings as I had before and it's doing 985 fps . I must have hit the FX Lottery with this new liner as it's Awesome accurate now....:)
 
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There is no doubt a superior liner can shoot a 33.95. Sold two Impacts and ironically both guys wanted the 600mm guns tuned for that pellet. I never fired a pellet out of an Impact up to that point so needless to say I pooped my pants after getting the setting dialed.
Yeah... My STD liner shoots H&N 36gr Slugs with fantastic accuracy..