Tuning FX Crown power slug upgrade kit install question.....answered.
- Thread starter qball
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Is this the correct way that the additional hammer weight slides onto the factory hammer?Guess no one installed one? I could not even find a video of this kit so guess I’m one of the first???
Anyhow the installation is quite simple by following Ernest’s Crown disassembly/assembly videos. The ADDITIONAL hammer weight slides into the factory hammer and replace the rear spring guide/seat with the new one that does not have the spring guide but recessed spring seat. Replace the factory probe with pin probe and done!
Tuned it and shot it yesterday, because of hammer weight almost doubled even with preload reduced by 3 revolutions the HS setting was only half way before the slug topped out on speed of 950fps and very soon after that over powering the valve and speed dropped. My worry of long dwell times didn’t really show up as I was able to easily find a setting to shoot 27.5 grain slugs at 940fps very consistently and accuracy. No issue reaching out to 200 yard gong and hit the 5 inch center reactive gong repeatedly. It’s actually bit faster than I would normally shoot out of a 600mm barrel but it’s shooting great so I left it.
Ordered a few boxes of heavier 22 NSA slugs so can’t wait to try them, I’ll be happy as a hog in mud if I can get the 35 grain to shoot near 900 fps. Not sure if crown can push a 22 slug that hard but I’m hopeful. At this rate I might as well get a 700mm barrel……doh!
BTW the slug power kit is FX factory kit with FX part number and all factory parts. Very happy with the kit except I want to try with a lighter hammer but that’s just me trying to split hair.
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With the hammer weight attached like this it is very hard tension to push the spring back to install the hammer adjuster on. Should it be this much tension or am I placing the hammer weight wrong ?
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The little metal tube is for the probe when used as .25 cal vs no tube as .22 cal.
The assembly should look like my original picture on the right with the hammer weight inside of hammer acting as spring guide.
The assembly should look like my original picture on the right with the hammer weight inside of hammer acting as spring guide.
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Bringing this back up as I just got the FX slug power kit along with a .25 cal 380mm barrel for my Crown. The Hammer weight wouldn’t fit in the hammer so the spring was out a lot further like was happening above, spring should be floating when you install the end cap. Seems like the hammer weight was just a little to tight so I chucked on my drill and ran it while holding 220 grit sandpaper on it until it would slide in then polished with 2000, worked fine after that.
Maybe the Hammer gets compressed after lots of shots? Seemed like it was maybe thousands of an inch to tight. Not sure why it wouldn’t fit but this is on a MK1 Crown, hopefully this will help someone else searching for info.
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Qball ,Guess no one installed one? I could not even find a video of this kit so guess I’m one of the first???
Anyhow the installation is quite simple by following Ernest’s Crown disassembly/assembly videos. The ADDITIONAL hammer weight slides into the factory hammer and replace the rear spring guide/seat with the new one that does not have the spring guide but recessed spring seat. Replace the factory probe with pin probe and done!
Tuned it and shot it yesterday, because of hammer weight almost doubled even with preload reduced by 3 revolutions the HS setting was only half way before the slug topped out on speed of 950fps and very soon after that over powering the valve and speed dropped. My worry of long dwell times didn’t really show up as I was able to easily find a setting to shoot 27.5 grain slugs at 940fps very consistently and accuracy. No issue reaching out to 200 yard gong and hit the 5 inch center reactive gong repeatedly. It’s actually bit faster than I would normally shoot out of a 600mm barrel but it’s shooting great so I left it.
Ordered a few boxes of heavier 22 NSA slugs so can’t wait to try them, I’ll be happy as a hog in mud if I can get the 35 grain to shoot near 900 fps. Not sure if crown can push a 22 slug that hard but I’m hopeful. At this rate I might as well get a 700mm barrel……doh!
BTW the slug power kit is FX factory kit with FX part number and all factory parts. Very happy with the kit except I want to try with a lighter hammer but that’s just me trying to split hair.
With the huma heavy hammer spring and the preload max out, pin probe , running a huma high pressure reg set at 170 , I'm getting 970fps with the a Neilson 29gr slug. I tried some 34 gr. Neilson slugs got 885fps but the accuracy was off a tad.
I'm in the process of laping a 1:18 twist barrel to see if that tightens up the grouping.
I expect to loss some fps due to added friction but hopefully gain tighter groups.
Also going to try spacing with Delrin washers to try to gain abit of the lost fps.
Continuing saga.
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It happens on the wildcats, also. If you hold your gun with barrel end up, the quickly point barrel down and you don’t hear that click noise from the floating weight, your hammer weight is then seized up inside the hammer. Your velocities will also be erratic
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Micro polishing helped mine . It worked for a year but dirt has worked its way into the system. Velocities have become slightly erratic. Std went from 2 to 4-6- up to 12
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Hi All.
My Crown 22 mk1 with 600 mm barrel in 22. / 700 mm in .17 and I have also worked to get the power up.
I am also using the larger Titanium valve seat and the larger valve.
Dual flow port and pin pellet probe.
Huma regulator mk3 and stronger hammer spring also gave extra power.
After all above modification the power max'ed out at 145 bar.
I started by ordering the kit with tungsten hammer . and it was way too heavy
Then I ordered a Dreamline hammer and 3 different additional weights.
I started by using my original hammer and the medium sized weight. too much.
Then i discovered that the hammer from the dreamline and from the crown was different.
So i used the combination with the medium weight and the the dreamline hammer.
Now I could shoot up to 160 bar but it became very very air hungry for the last extra Fps.
So I am now using the Dreamline hammer with the lightest additional weight (the one with a thin skirt)
I get now 50 fps more at 140 bar and it is not too airhungry. But now it shoots way too hot for garden pellet shooting even with minimum hammer wheel.
I have to shoot heavier pellets to keep the speed below 900. I can lower the speed by removing the stock and do the fiddle with the allen key screw. But I just hate that. so i leave the allen key where it is now.
Now it shoots knockouts in .22 at 975 fps and I shoot Zan 16 gr. slugs in .177 with 700 mm heavy liner at 940 fps too. and it is as accurate as my Redwolf.
I now came to the conclution more power than i have now means buying a new rifle....
Claus
My Crown 22 mk1 with 600 mm barrel in 22. / 700 mm in .17 and I have also worked to get the power up.
I am also using the larger Titanium valve seat and the larger valve.
Dual flow port and pin pellet probe.
Huma regulator mk3 and stronger hammer spring also gave extra power.
After all above modification the power max'ed out at 145 bar.
I started by ordering the kit with tungsten hammer . and it was way too heavy
Then I ordered a Dreamline hammer and 3 different additional weights.
I started by using my original hammer and the medium sized weight. too much.
Then i discovered that the hammer from the dreamline and from the crown was different.
So i used the combination with the medium weight and the the dreamline hammer.
Now I could shoot up to 160 bar but it became very very air hungry for the last extra Fps.
So I am now using the Dreamline hammer with the lightest additional weight (the one with a thin skirt)
I get now 50 fps more at 140 bar and it is not too airhungry. But now it shoots way too hot for garden pellet shooting even with minimum hammer wheel.
I have to shoot heavier pellets to keep the speed below 900. I can lower the speed by removing the stock and do the fiddle with the allen key screw. But I just hate that. so i leave the allen key where it is now.
Now it shoots knockouts in .22 at 975 fps and I shoot Zan 16 gr. slugs in .177 with 700 mm heavy liner at 940 fps too. and it is as accurate as my Redwolf.
I now came to the conclution more power than i have now means buying a new rifle....
Claus
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Good tuning there. My conclusion after my Crown is almost as powerful as my Impact is: I needed another Crown to shoot pellets.
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Indeed sounds like something very similar to what I experienced.
Hello everyone,
Last time I saw this topic passing by, was more than 6 months ago. Now by coincidence seeing some comments have been added, so I ve been reading up a bit. Feeling a bit surprised that even today some of the .22 Crown shooters would still be tempted to go adding a massive 13 gram weight to their factory Crown hammer.
In recent 2 years have been extensively testing (in my .22 Crown II) 4 different hammer springs combined with some 8 homemade hammer weights varying from 4,5 grams up to 11,75 grams, some in RVS, some in brass; with varying lenghts of the hammer weight bodies as well as varying head hights of the respective weights. Also that latter aspect is a more important factor than one might suspect, at the moment one goes 'breaking into' the Crown's subtle factory balance and the purpose it was intended and designed for : great HP accuracy on a limited plenum, at the same time each shot with high air efficiency .
Today here using a mere 6 gram hammer weight added to the 16 gram factory hammer. The spring used to ‘drive’ this total of 22 gr hammer weight has about a good 10% higher powercurve than the FX 11500 factory spring. This somewhat stiffer spring releases its preloaded energy a fraction of a second faster than the FX 11500 spring, subsequently also returning to ‘resting position’ a tiny bit faster.
This so called 'power spring' is 'sitting' in a 2,75 mm deep seat, milled out in one of the modified spare hammer spring guides I had bought to experiment on. (see earlier post). I have tried several modified models of FX factory hammer spring guides, both with (shortened) hammer spring stem and without stem. Those spring guide blocks with entirely cut of stems always came out of the tests with poorer results, both in terms of shots per fil, as to ES numbers over larger shot strings, hence also in accuracy (over longer strings).
Here ’s why I ‘m today surprised at reading that .22 Crown shooters are apparently using the rather ‘brutal' power kit with a massive 13gr extra hammer weight on top of a 11500 factory spring, sitting on a hammer spring guide body with its stem completely cut of, while at the same time eating away some of the hammer’s travel length due to the large head hight of the used hammer weight :
From the testing I ve done, this sort of configuration proves itself more of a disadvantage than anything else, when shooting .22 in up to 30 grains.
Long story short(er) :
Even at a mere 130 bar regulator setting and with the shuttle screw merely turned out 4,55 mm, still allowing for some serious hammer travel length, my .22 sends off pin probe loaded 25 grain R.Monsters (and H&N slugs) at a max of 302-303 m/s (approx. 995fps). Slightly tuned down to 292-293 m/s (960 fps), both R.Monsters and H&N 25 grain have shown outstanding outdoor accuracy at 100 yards and 100 m.
Turning up reg pressure to 140 – 150 – 160 bar while each time adjusting preload by inserting the appropriate shuttles (each of them with their pre-tested and preset shuttle screws, I have established that shooting heavier .22 lead poses no problem whatsoever, still using the same 6 gram extra hammer weight added on a slightly stiffer spring. Moreover, air usage per shot always remains optimal, resulting in the highest possible number of shots per fil.
Conclusion simply being : there s alternatives for the massive 16 + 13 gram hammer weight 'power kit'.
Imo this kind of 'massive hammer mass' configuration might possibly make sense for those few wanting to shoot heavy .30 slugs at 160-170bar (on an adapted regulator). But when shooting lead up to about 30-32 grains out of a .22 Crown, this 16+13gr massive hammer mass is more like an ‘overkill’ generating more disadvantage than advantage.
Btw, as a last note :
Out of a standard superior, the heaviest lead i m shooting is 25 grain. For those wanting to shoot 27 grain and up, a superior heavy liner is the way to go.
My 2 cents anyway.
But after all is said and done, everyone should foremost do their own. No conviction greater than your own conviction derived from trial and error practice.
Good luck.
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I've got what seems to be a (weirdly) fantastic tune on my mk2 for 18grain JSBs, shooting them at 950 fps. I'm running the reg at 95 bar using the 700mm barrel and Huma slug kit with 13.2 gram hammer weight (although I don't use slugs), with power wheel low. My extreme spread is a bit high at approx. 15 fps, but it doesn't seem to impact my groups. I shoot at 50 - 75 meters. The high shot count is great for a weekend on the bench.
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Now THIS is the post I’ve been looking for since the end of last year!!!!!
FANTASTIC information, thank you. This para “Even at a mere 130 bar regulator” is exactly what I’ve been trying to do. I will have to go through it a few more times in order to, hopefully, work out exactly what I will have to get to make this a reality.
From what I can understand, the pic with the brass hammer are the things you changed, correct?
@Ex.Magnum there will be more questions in the not-too-distant-future….if you don’t mind.
Thanks in advance.
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The issues with a lot of comments is mixing up slug weight/speed and hammer weight. While related but slug weight/speed is a mere product of hammer/spring and regulator setting, heavier hammer must be pair with reg pressure they are designed for. By just adding a heavy hammer without setting correct reg pressure for the additional weight you will actually lose speed on top of inefficiency.
Let me see if I can break it down a bit simpler:
Reg below 145-150 bars - stick with factory settings, just crank up the preload.
Reg reg between 155-170 bars - get heavier hammer you can experiment with 7-14 grams
For reference: With my 600mm barrel and 150 bars my crown MK2 can shoot 27.5 grain NSA @ 920fps basically maxed out. Same 600mm barrel and 160 bars using heavier hammer I was shooting 35 grain NSA @920fps.
Simpler answer/template would be if you want shoot heavier slugs from crown then get 700mm barrel, power slug kit, 160-170 reg. Slugs lighter than 27.5 grain then stick to 150 bars, factory hammer, and 600-700mm barrel. 500mm barrel can work but just maxes out top speed lower or use lighter slugs, crown with 500mm 22 barrel with factory hammer and 150 reg can still easily shoot 23 grain NSAs at over 900fps. When shooting slugs use reg lower than 145 bars at your own risk.
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You might just even go a lot simpler than that in order to reach high velocity with 18 grains at a 95 bar reg setting.
This next one is a tune I ‘stumbled upon’ when receiving my MK2 straight from the factory :
• As said, regulator set at a mere 95 bar;
• 600 mm superlight (with a standard superior);
• No extra hammer weight (just plain factory hammer);
• Non-customized, standard factory spring guide;
• Factory hammer spring (no 11500);
• Shuttle screw only 1,9 mm turned out;
• And an added FX spacer ring no 20136 under the hammer spring; (yes indeed, straight from the factory, with that spacer on the spring guide)
This is the spacer i m talking about :
When the dealer handed over my MKII , I opened the case to inspect the gun (right there and then in the shop), and found a small FX note inside reading “HP” followed by some other scribbling I couldn’t decipher, and neither could the dealer. When subsequently looking at the reg mano I was immensely surprised at seeing it displaying but 95 bar. I went like “what’s this then? HP on just 95 bar?” Couldn’t make much of it so the first thing I did when reaching home, was loading up a magazine with 18 gr JSB’s.
The chrony values at that point really surprised me. With the power wheel fully open, the 18 grains straight away went to 293-295 m/s (that's about 960-965 fps).
However, that snappy bark coming out of the gun at that point, was just a bit too shrill. Valve not closing fast enough. After turning down the power wheel, velocity settled at some 282-283 m/s (that ‘s about 925-930 fps), delivering great bullseye accuracy at 70 m target distance (that’s about 75 yards).
Later testing confirmed a massive shotcount. From a 250 bar fill down to 95 bar reg pressure, way over 200 shots per fill from a 480cc bottle.
One week after, i put a 700 cc Alsafe on. Never counted those shots per fill, but it must have been a crazy lot.
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That sounds spot on! Makes a lot of sense. Thanks for that, now I'm tempted to give it a try... it's perplexing though, how much variance there is on Crown IIs from the factory. My reg was set at 160 bar from new (dealer bought). I guess that it is absolutely assumed the buyer will be tinkering from day 1.You might just even go a lot simpler than that in order to reach high velocity with 18 grains at a 95 bar reg setting.
This next one is a tune I ‘stumbled upon’ when receiving my MK2 straight from the factory :
• As said, regulator set at a mere 95 bar;
• 600 mm superlight (with a standard superior);
• No extra hammer weight (just plain factory hammer);
• Non-customized, standard factory spring guide;
• Factory hammer spring (no 11500);
• Shuttle screw only 1,9 mm turned out;
• And an added FX spacer ring no 20136 under the hammer spring; (yes indeed, straight from the factory)
This is the spacer i m talking about :
When the dealer handed over my MKII , I opened the case to inspect the gun (right there and then in the shop), and found a small FX note inside reading “HP” followed by some other scribbling I couldn’t decipher, and neither could the dealer. When subsequently looking at the reg mano I was immensely surprised at seeing it displaying but 95 bar. I went like “what’s this then? HP on just 95 bar?” Couldn’t make much of it so the first thing I did when reaching home, was loading up a magazine with 18 gr JSB’s.
The chrony values at that point really surprised me. With the power wheel fully open, the 18 grains went to 293-295 m/s (that's about 960-965 fps).
However, that snappy bark coming out of it at that point, was just a bit too shrill. Valve not closing fast enough. After turning down the power wheel, velocity settled at some 282-283 m/s (that ‘s about 925-930 fps), delivering great bullseye accuracy at 70 m target distance (that’s about 75 yards).
Later testing confirmed a massive shotcount. From a 250 bar fill down to 95 bar reg pressure, way over 200 shots per fill from a 480cc bottle.
One week after, i put a 700 cc Alsafe on. Never counted those shots per fill, but it must have been a crazy lot.
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