Tuning Maverick .22 cal sniper wrong hammer weight

[Centercut]

Which lightweight slugs did you try to shoot? What brand and weight? Was the slug very tight and hard to push into the breech? The Superior liners have a VERY tight choke compared to the older STX liner or Slug A liner.

FYI, the Impact maxes out in .22 caliber at about 135 bar. So were you to do the same thing you did with your Maverick and adjust to 150 bar (indicated, could be 10 bar higher due to gauge inaccuracy), the same thing may have happened. So this isn’t a new issue. 

 

[qball]

So the way I read it is the gun came with the right hammer weight for 22 and OP wants to push it further with slugs and increased regulator to max. I think I’ll side with FX on this one because that’s not how the gun was tuned and shipped. 


To OP: however unless you shootings 33 grain slugs I don’t think you need it, have you tried 120-130 bars? With that big of a plenum you shouldn’t need 150 bars, that’s for .25 and 30 caliber which is the hammer weight you are buying for. 

 

[Jayman07770]

I was using the FX hybrid slugs. After unplugging the two stuck slugs I lower the regulator to 100bar and started working the pressure up. Around 125bar the FPS started to drop. At this point there was more pressure pushing against valve than what the hammer strike could handle. I wasn’t going to attempt raising the regulator pressure any higher and get another slug stuck again. When the new hammer weight get here I’ll test it up to 150bar. 

 

[Centercut]

So before the speed started to drop off, you got to what, 1000 FPS? You do know that The FX hybrids work best in the 950 to 960 FPS range, right?

I shoot a .25 caliber Impact with 43.5 grain NSA slugs, and shoot them at 900 FPS... My reg. pressure is 130 bar - no hammer weight and stock hammer spring. That's 78 FPE. I do have a larger (Ernest Rowe) transfer port and FX pin probe, plus lighter valve spring.

Mike

 

[Jayman07770]

The FX Hybrids max FPS was around 940-947 and regulator 120 ish bar on the Maverick. I haven’t gotten a chance to test what speed this rifle prefers. Both my 500mm and 600mm Impacts prefer the hybrids at different speeds. 

 

[Jayman07770]

Update:

FX made it right and refunded my order. 

 

[stoti]

I know it’s apples and oranges but we have a .25 Maverick and were slinging the 33.95 JSB’s at 935fps on Sunday with our rear reg. at 145 bar and the front reg. at 175 bar. I would think if we shot the 26gr. Hybrid slugs, which we are going to today, they would be flying at somewhere around 980-1000fps. With a .22 and those light little Hybrids, I would think even with the standard, light hammer and reg. set around 120 bar you could shoot them pretty darn fast. 

I’m not trying to be condescending at all, just trying to help remedy the problem...You had the power wheel set with the 7 and it was on the bottom? You backed out the hammer spring (counterclockwise) to increase power. With the Impact, it’s opposite, you compress it. And something we didn’t do quite often while adjusting our gun...After you used the 1.5 allen key to adjust the hammer spring, you turned the wheel back to 7? We adjusted out hammer spring multiple times and then fired the gun while the wheel was on minimum instead of turning it back to 7. It spit the pellet at 600fps instead of 900fps and at one point we thought we stuck one in the barrel too. We didn’t but with the wheel on low, the power drops significantly. I can see people doing that a lot because you have to adjust the wheel to low power to adjust the hammer spring and then move it back to 7 before shooting. 

What are the weight differences between the regular and “slug” hammer?

Have a nice day and good luck?

Stoti







Sorry, I was typing while you just posted your reply.

 

[Jayman07770]

From what I’ve been told it’s just the .22 cal. Your .25 cal may already have the heavier hammer weight. The PW was in the correct position and Allen screw turned CCW. I’ll measure both the hammer weights when the new is in. 

 

[Nnauerz]

My Maverick Sniper shoots 23 grain .217 javelins at 968 fps with the reg set to just over 110 with a huma gauge not sure how accurate the gauge is but it does have a line for every 10 bar instead of every 50. only mod is the Huma dual hole transfer port. Also how can i tell if mine has the wrong weight. how much should it weigh?

 

[Jayman07770]

My Maverick Sniper shoots 23 grain .217 javelins at 968 fps with the reg set to just over 110 with a huma gauge not sure how accurate the gauge is but it does have a line for every 10 bar instead of every 50. only mod is the Huma dual hole transfer port. Also how can i tell if mine has the wrong weight. how much should it weigh?

I was getting around 935fps with the 23gr NSA .217 and factory transfer port. I’ll weight both the hammer weights when it comes in today and let you know the difference. 

 

[Jayman07770]

The hammer weight I had is 94.1gr and the heavier hammer weight is 204 gr. 

I also discovered the slot machined for the safety Allen screw was filed down but not far enough to completely engage the switch. It barely stopped the trigger and only works if you don’t apply heavy pressure to the trigger. 


After replacing the hammer weight and doing no other changes I got 944 FPS with 23gr NSA .217. Than I bumped the 1st reg to 175-180bar and 2nd reg to 150bar. 
23gr NSA .217 1000-1012 fps

26gr JSB KO around 984 FPS

I’ll switch the TP to a Huma and see how much FPS it will grain. 


For reference my Impact with PP, 22cal 600mm barrel, NSA probe, and Huma TP is pushing the .26gr KO at 1,000 FPS with the reg at 150bar on PW MAX. 

 

[Nnauerz]

Wow that's a huge difference is the smaller one maybe meant for sub 12 ft lb. ?

 

[Jayman07770]

The lighter hammer weight is meant for 18g pellets and high shoot count. Both of the hammer weights have their purpose. If you got the lighter hammer weight than keep your regulator pressure under 125bar. 

 

[Nnauerz]

Just check mine also has the lighter hammer and the relief cut for the safety is different.

 

[Jayman07770]

That’s very interesting, FX must of used different main blocks. Yours looks like a finished product while mine looks like a modified prototype. I had to tape up the block than use a demel tool to lengthen the slot forward for the safety to fully engage. Good thing I checked because my safety didn’t really work as intended. 

 

[qball]

There are 3 hammer weight, light medium and heavy. Mine came with light and most likely install the medium. I’ll post pictures when I get mine but it won’t be till after Christmas

 

[Nnauerz]

Do you have a part numbers for all three ? 

 

[qball]

Do you have a part numbers for all three ?

the sales invoice didn’t have part number so hope when they come the bags will have them. Just call FX and ask for maverick hammer weights, they would know. 

 

[Jayman07770]

This is probably the hammer weight part numbers. 

 

[Bldermike]

 Hi Guys

I found out with my MkII impact that the gauges are garbage! So right of the bat one was 20 bar off so I went to Huma and purchased a digital gauge tester and two new gauges. Save yourself a lot of time and get one of the tester gauges from Huma! I have the compact .22 Maverick and the reason I purchased the compact was to have a short 500mm barrel. I have a 700mm and 580cc tank to make it a sniper. The set up was with the digital gauge. I put the 700mm barrel on and this what I am getting.

160 bar 1st 130 2nd gauges Hammer Maxed out (7)1055 fps (6)1035 (5)1011 (4)990 (3)872 (2)826 (1)761 18.13gr JSB. Hope this helps.