Tuning Impact reg. pressure/tune to shoot 40 grain .22 caliber slugs

If the shirt is deeper, material is moved to a different part of the projectile. In my experience directly impacting flight. 
It’s like the mk2 king heavy. Slightly different geometry. Bc is worse. And in all my guns I get more flier when shooting them.

Good call I didn't think about that weight would be moved forward or backwards
 
Pretty sure the SA guys have their guns fully hot-rodded with every possible airflow mod/upgrade to get those speeds. I also saw at least one reg pressure at 190b. I suspect they may be using all 0.6mm belleville springs in the stack to do that (the stock FX AMP stack is about 50/50 0.5mm and 0.6mm). If you look at Huma, they spec a full stack of 0.6mm for their reg at 200b.

The guns sound NASTY in the videos, so I can only imagine what they sound like in person.
 


My gun shoots well at 60 to about 65fpre , when I max it out say 70sFPE my shot count and accuracy suffer greatly ,



LOU


that is clear indication that your valve isn’t closing when the slug leaves the barrel so the air pressure in the chamber/barrel dramatically drop which speeds up air rushing out from the valve. Not only you waste a lot of air the extra air creates turbulence and slugs are very sensitive to muzzle turbulence so the accuracy goes down to the toilet. Only way to gain more speed is to get longer barrel or/and higher reg pressure. 
 
So I think we’ve decided:

- high pressure reg or reg Belleville washer setup (180 bar up to 210 bar)

- heavier hammer spring

- heavier hammer weight

- longer barrel - at least 700mm

- larger diameter valve / valve seat

- lighter valve spring

- larger transfer port 

- pin probe for slugs 

- a few hundred (or more) slugs to tune the gun

Bottom line is to get 1000 fps from a .22 Impact shooting 40 grain slugs off the shelf is definitely a pipe dream. Perhaps if you’re handy and do the work yourself you’re looking at $500 and to have the gun tuned this way by a pro significantly more?
 
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So I think we’ve decided:

- high pressure reg or reg Belleville washer setup (180 bar up to 210 bar)

- heavier hammer spring

- heavier hammer weight

- longer barrel - at least 700mm

- larger diameter valve / valve seat

- lighter valve spring

- larger transfer port 

- pin probe for slugs 

- a few hundred (or more) slugs to tune the gun

Bottom line is to get 1000 fps from a .22 Impact shooting 40 grain slugs off the shelf is definitely a pipe dream. Perhaps if you’re handy and do the work yourself you’re looking at $500 and to have the gun tuned this way by a pro significantly more?

And there’s the question, what impact does that have on the actual gun. The components are absolutely not built for that.
 
Yes sir, Mr Corny. Good reply, as for sure part’s lives will shorten. Parts aren’t cheap, either, as an example a recent rear block replacement was close to $200 with shipping.

ive never been one to put shot count high on my list until recently, but getting only 6-12 shots out of a 28 round side shot mag(and a 580cc bottle, lol!) doesn’t sound appealing to me. 


Not to mention stocking up on regulator rebuild parts
 
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Testing all the bolt ons, 800mm barrel, power block, hammer, etc,today but don’t have improved regulators so setting rear close to 165 - 170 and getting 1014 fps, there is a long wait between shots b4 the rear is back on pressure. These are the speeds for 40gr .22 at the moment. Will test accuracy in the morning and post

A504D57C-5B81-4C41-97DA-EF88E38CE16F.jpeg




0599FF9F-7316-4169-AE66-D024A3332459.jpeg
 
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I've seen the South Africans shooting the new H&N 40 grain slugs at 1000(?) FPS (90 FPE), and am wondering how high of a reg. pressure is used, if the reg. is stock, what sort of hammer spring and weights are used to get this FPE and overcome the high back pressure on the valve?

The reason I ask is that I had recently tuned a .22 Maverick, and used the .30 hammer weight with the power kit weights (washers), Ernest transfer port, Superior Heavy liner, 155 bar reg. pressure, and got about 950 FPS with NSA 31.2 grain slugs (62.5 FPE).

So can someone explain the magic to get 90 FPE from a .22 caliber Impact (I'm assuming is like 180 to 190 bar reg. pressure and all that goes with it)? Is it reliable? Heavier valve components and high pressure reg.?
Im wondering this myself, and im starting to feel like all the youtube videos are marketing to sell guns based on vaporware. Ive got a 700mm m3 with heavy liner that just one holed 31.2 nsa at 915 fps and the same with javelin 23s at 990... But i needed more. 160bar plenum pressure, huma heavy spring, 14.4 grain hammer (allegedly tungsten but i think its just an odd heavy alloy because the back of a utility knkfe blade produced a shaving) and it seems maxed out at 1007 fps for 31.2 nsa and the hammer spring adjuster is useless as it wants to be at minimum setting for best results. The spring may come out and stock put back in if it refuses to group. Barrel whip is a thing for me so i made a sort of tensioning system for my shroud, which the principle of you guys are probably very well aware of. The heavy spring makes me wonder... But if it gets me close to 1100 next range day, i will live with it. 23s just shoot so dang good other than wind, i might just forget the power pig endeavor.
 
Yes sir, Mr Corny. Good reply, as for sure part’s lives will shorten. Parts aren’t cheap, either, as an example a recent rear block replacement was close to $200 with shipping.

ive never been one to put shot count high on my list until recently, but getting only 6-12 shots out of a 28 round side shot mag(and a 580cc bottle, lol!) doesn’t sound appealing to me.


Not to mention stocking up on regulator rebuild parts
I fell for the powerblock marketing, as i have an early m3. The only changes are to the valve body as best i can tell, i didnt blueprint it. The i-d of the valve body increased and the 4 milled slots around its circumference are gone. The aluminum parts matched what was supplied with my impact. Your toyally right about availability and cost. Im going to have to get reg parts.
 
Unrestricted the airpath.
I don't know anything about M3, I have the MK2 PP only. I remachined one rear block transfer hole from a 6.5mm ID hole into a 7.3x9.0mm slot, also the Valve House 6.5mm ID hole enlarged to 7.3mm. These changes needed a bigger peek poppet, at first attempt I made it 9.3 mm OD but that restricted the air flow inside a 10mm ID tunnel, so I recut to 8.3mm OD. Without these not much gain if playing with heavy hammer or springs only. But a combination with all - you get a monster.
Just my story that I was there:
Not a .22 but a .25 x700 Superior Heavy. @ 141 bar on Reg 44gr ZAN 1050 fps and still about 2mm play on the HS tensioner. 46 ZAN 1020+.
And finally I decided going back to pellets, not happy with slugs POI at all @ 100 meters. These days reversed the power and the re-tunning for pellets is scheduled for a weekend. My dream was wrong, I wanted the slug shooting machine badly, and just a disappointment after a half a year and $$$ spent trying.
 
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Unrestricted the airpath.
I don't know anything about M3, I have the MK2 PP only. I remachined one rear block transfer hole from a 6.5mm ID hole into a 7.3x9.0mm slot, also the Valve House 6.5mm ID hole enlarged to 7.3mm. These changes needed a bigger peek poppet, at first attempt I made it 9.3 mm OD but that restricted the air flow inside a 10mm ID tunnel, so I recut to 8.3mm OD. Without these not much gain if playing with heavy hammer or springs only. But a combination with all - you get a monster.
Just my story that I was there:
Not a .22 but a .25 x700 Superior Heavy. @ 141 bar on Reg 44gr ZAN 1050 fps and still about 2mm play on the HS tensioner. 46 ZAN 1020+.
And finally I decided going back to pellets, not happy with slugs POI at all @ 100 meters. These days reversed the power and the re-tunning for pellets is scheduled for a weekend. My dream was wrong, I wanted the slug shooting machine badly, and just a disappointment after a half a year and $$$ spent trying.
Im realizing the same this morning, maybe i will re machine my original block and valve body a little down the road. Im gonna try just the heavy hammer and it might get me where i wanted to be, high 900 fps with 31s instead of chasing the bc increase ted saw. My group went from sub moa to just over moa with 50ft lb 23s which i cannot abide theyre not predictable enough, before they were stackable. Harmonic shroud, ronin and home brew tensioning system made the 700 a death ray and i couldnt leave well enough alone thanks to wanting to shoot 200 yard precision. The gun's adjustments were previously maxed out for 31 nsa and the heavy spring seems to be messing up things more than helping. I may need to stay around 60 ft lb max energy and slower 31s. Taking a many year break from the forum may have cost me.
 
They should outlaw any manufacturer reps from producing videos, with anything that's not commercially available. People see this stuff, take in tidbits, or don't fully understand, and think they can go buy an impact and a nexus, and shoot the same as what they just saw on youtube. They don't show the days and days of tinkering, piddling modifying, and racing up that gets done behind the scenes. Or the years of experience behind the trigger. They just show the final outcome of their R&D. Now someone not affiliated, or paid by the company their racing with, more power to ya.
 
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Pretty sure the SA guys have their guns fully hot-rodded with every possible airflow mod/upgrade to get those speeds. I also saw at least one reg pressure at 190b. I suspect they may be using all 0.6mm belleville springs in the stack to do that (the stock FX AMP stack is about 50/50 0.5mm and 0.6mm). If you look at Huma, they spec a full stack of 0.6mm for their reg at 200b.

The guns sound NASTY in the videos, so I can only imagine what they sound like in person.
Ted says in there, it's way loud. that the video isn't doing the noise justice...
 
Im realizing the same this morning, maybe i will re machine my original block and valve body a little down the road. Im gonna try just the heavy hammer and it might get me where i wanted to be, high 900 fps with 31s instead of chasing the bc increase ted saw. My group went from sub moa to just over moa with 50ft lb 23s which i cannot abide theyre not predictable enough, before they were stackable. Harmonic shroud, ronin and home brew tensioning system made the 700 a death ray and i couldnt leave well enough alone thanks to wanting to shoot 200 yard precision. The gun's adjustments were previously maxed out for 31 nsa and the heavy spring seems to be messing up things more than helping. I may need to stay around 60 ft lb max energy and slower 31s. Taking a many year break from the forum may have cost me.
Hey, I found that with the barrel tensioner, power block and hammer u can get the gun pretty accurate, I was shooting 40gr Javlins at average 1000 fps to make this 200meter shot in wind, attached video. But since then I added the clamp that goes with the top rail, the clamp is supplied by Saber Tactical as the clamp is different on the 800mm barrel. Also went for a rear Huma reg and with the pressure at 180 on the rear reg I’m getting 1020 and it’s grouping in the same hole at 40meter with 40gr Slugs, attached pic

AB0DAEA9-54AB-486F-BBF3-6C9647CA4FA5.jpeg


 
They should outlaw any manufacturer reps from producing videos, with anything that's not commercially available. People see this stuff, take in tidbits, or don't fully understand, and think they can go buy an impact and a nexus, and shoot the same as what they just saw on youtube. They don't show the days and days of tinkering, piddling modifying, and racing up that gets done behind the scenes. Or the years of experience behind the trigger. They just show the final outcome of their R&D. Now someone not affiliated, or paid by the company their racing with, more power to ya.
Well said! Especially with the vapor ware prototype stuff they use. I went from a marauder mk1 to an impact m3 thinking it would have the power potential advertised and precision right out of the box. Days of tuning tinkering and finding the root of inconsistencies later im close. The marketing on slug liners is over stated too. You can shoot 150 yards with a pellet liner and light slugs all day long.

As my shooting buddy and i are learning, a 500mm maverick with a heavier hammer weight will do exactly what a box stock 700mm impact will do cranked up when both are harmonically tuned (energy and accuracy) and the mav is way easier to swap a hammer weight.
Im beginning to suspect hammer weight increase and harmonic barrel tuners are the best money spent. I shouldve known better with my experience in harmonic tuning powder burners.
 
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