Weihrauch HW100 .177 regulator tuning

Merry Christmas everyone!!

When I received my new .177 HW100 a few days ago, I was getting 1000 fps with the Air Arms 10.3 gr pellets.

I backed the hammer spring tension until I got around 880 fps with the same pellets.

The problem now is that the spread from a full tank to an empty tank is about 50 fps...

Let me explain... At 200 BAR my speeds are right at 860 fps and at 120 BAR the speeds have increased to 910 fps...

I'm thinking to DECREASE the regulator pressure down a bit and, if need be, INCREASE the hammer spring back up to get the 880 fps I'm looking for.

Any thoughts...?!?!

Thank you :)
 
Is it consistent from 200 BAR down to 150 BAR? And then starts to rise sharply below that? If so, your regulator is probably just set too high.

If its all over the place rising or falling from 200-150, then the regulator isn't working just right. The regulators on these guns do not work like traditional regulators on most guns, and they need little to no break in time. It's either right or it's not.
 
I have the same rifle, and mine was also shooting hot. Yep, try backing down the reg pressure. I went all the way to a 12 fpe rifle with mine, shooting the 10 g pellet a little over 700 fps. Now I get great consistency, and an 80+ shot count on reg. I think the sub 12 ft lb is where it really shines. But, you can probably get what you want with a little less reg pressure. If you get bored, back it down to the non-FAC level, you might like it.
 
Got it fixed !!

I tried closing the reg by 1/4 turn from stock and adjusting the hammer spring to give me a starting speed of 875 with the 10.3 gr pellets.
It didn't work... the overall spread got much worse and speeds creeped upwards of 936 fps.

So I did the opposite...

I opened the reg by 1/4 turn from the stock setting, which I had previously marked, and reduced tension on the hammer spring to give me a starting speed of around 880 fps. I then fired 70 shots from 200 to 120 BAR, and as you see below, my average speed was 888 fps with an extreme spread of 26 fps.

This is an amazing rifle and I'm very thankful to Jerry McGee for having suggested it !! BTW, this rifle works best without the moderator and the best pellet so far has been the AirArms FT 10.3 gr 4.52mm pellets. The group bellow are 6 shots from 30 yards. Have a great Christmas :)

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The HW100 in .177 probably runs a bit too “hot” with the 600mm barrel (vs. the 410mm barrel) for the 10.3g pellets.

You might want to try 13 grain JSBs in it….
Not at all, got them down to 888 fps which is perfect for FT. Check out the info above. I'll try the 13s as well though. Now that I understand the tuning process on this rifle, I could have easily tuned it to sub 12s. I just ran 84 pellets through it back to back with a ES of only 28 fps, from 193 BAR to 105 BAR. See photos below. The first shot was 881 fps and the last 84th shot was 900 fps, and all that on a 175cc tank. An Amazing rifle for sure :)
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Not at all, got them down to 888 fps which is perfect for FT. Check out the info above. I'll try the 13s as well though. Now that I understand the tuning process on this rifle, I could have easily tuned it to sub 12s. I just ran 84 pellets through it back to back with a ES of only 28 fps, from 193 BAR to 105 BAR. See photos below. The first shot was 881 fps and the last 84th shot was 900 fps, and all that on a 175cc tank. An Amazing rifle for sure
I think EPG was referring to the typical factory tune, and I think he is correct, as your experience supports. My carbine model arrived shooting the 10 g about right, around 880 fps, but I have since tuned it down to the sub 12 fpe level.
 
I think EPG was referring to the typical factory tune, and I think he is correct, as your experience supports. My carbine model arrived shooting the 10 g about right, around 880 fps, but I have since tuned it down to the sub 12 fpe level.
Yep, exactly what I was referring too - factory ”FAC” tune with 600mm barrel may be a bit too hot for 10.3g.

Yes, its very easy to tune these rifles - I have lots of experience. I’m currently shooting my .22 with 600mm barrel at 715fps with lightweight 14.66g H&N FTT pellets. I love the trigger, silencers, everything about these rifles - but they are even better at 680-720 fps vs. 870-900fps power levels.
 
Yep, exactly what I was referring too - factory ”FAC” tune with 600mm barrel may be a bit too hot for 10.3g.

Yes, its very easy to tune these rifles - I have lots of experience. I’m currently shooting my .22 with 600mm barrel at 715fps with lightweight 14.66g H&N FTT pellets. I love the trigger, silencers, everything about these rifles - but they are even better at 680-720 fps vs. 870-900fps power levels.
I agree. My .177 at a little over 700 fps makes a great yard rifle, and still plenty of power for squirrels inside 40 yards. The additional benefits of the sub-12 tune, it's virtually silent (good for the neighbors), and the shot count is about 4X the factory FAC tune. When we stretch these rifles beyond their original design parameters, there are consequences. And yes, the trigger is very good, one of the few real two-stage triggers available. Mine is reliable at 6 ounces, but I would bump it up for hunting.
 
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Not sure you guys noticed that I actually OPENED the regulator by 1/4 turn to get more consistency in my shots - 30 fps spread over 84 shots (see photos).
And, I backed the hammer spring to get the desired 880 fps speed. With the factory tune I was getting more than 60 fps spread in only 70 shots fired.

I am thinking about opening the regulator 1/8 turn more and backing the hammer spring to keep speeds at 880 fps, to get even more consistency...
My only concern is that by backing the hammer spring too much I'm slowing down the "lock time" and that could hurt accuracy.
 
Seems like your reg is still a little bit high, turn it down a little bit more, around 105b (I use it at 115 with the shorter barrel and I get 60 consistent shots at thst dame power)
Not sure you guys noticed that I actually OPENED the regulator by 1/4 turn to get more consistency in my shots - 30 fps spread over 84 shots (see photos).
And, I backed the hammer spring to get the desired 880 fps speed. With the factory tune I was getting more than 60 fps spread in only 70 shots fired.

I am thinking about opening the regulator 1/8 turn more and backing the hammer spring to keep speeds at 880 fps, to get even more consistency...
My only concern is that by backing the hammer spring too much I'm slowing down the "lock time" and that could hurt accuracy.
 
Miguel, I can't tell from your comments where your tune balance stands, which I have found to be critical. Usually, around 95-97% of the maximum velocity at any given reg setting will result in the best balance. So if you want 880 fps, your best reg set point will probably produce around 900-925 fps at the maximum HST. My ES on the HW100 is often less than 10 fps, and I've had similar results with other rifles using this method of balancing the tune. I don't think you need to be concerned with lock time variations caused by different HST settings. Theoretically, a slower hammer spring could negatively impact accuracy, but I think that's getting into an area of very fine detail that is not likely to be observed in practice. Proper hold and trigger technique will, I believe, more than offset any slight difference in lock time.
 
Miguel, I can't tell from your comments where your tune balance stands, which I have found to be critical. Usually, around 95-97% of the maximum velocity at any given reg setting will result in the best balance. So if you want 880 fps, your best reg set point will probably produce around 900-925 fps at the maximum HST. My ES on the HW100 is often less than 10 fps, and I've had similar results with other rifles using this method of balancing the tune. I don't think you need to be concerned with lock time variations caused by different HST settings. Theoretically, a slower hammer spring could negatively impact accuracy, but I think that's getting into an area of very fine detail that is not likely to be observed in practice. Proper hold and trigger technique will, I believe, more than offset any slight difference in lock time.
Excellent news, thank you very much for taking the time to help. My first FT match is coming up on the 8th...

Could you walk me through the process of tuning this thing? Considering that the only tool I have is a chronograph.
I'll send you a PM with my cell just in case it's better for you to explain it via phone...

Thank you very much!!
 
Not sure you guys noticed that I actually OPENED the regulator by 1/4 turn to get more consistency in my shots - 30 fps spread over 84 shots (see photos).
And, I backed the hammer spring to get the desired 880 fps speed. With the factory tune I was getting more than 60 fps spread in only 70 shots fired.

I am thinking about opening the regulator 1/8 turn more and backing the hammer spring to keep speeds at 880 fps, to get even more consistency...
My only concern is that by backing the hammer spring too much I'm slowing down the "lock time" and that could hurt accuracy.
Yes sir by what you call opening is actually decreasing the pressure the reg is operating at! Closing increases the pressure! So your on the right track!
 
Yes sir by what you call opening is actually decreasing the pressure the reg is operating at! Closing increases the pressure! So your on the right track!
Chuck, let me see if I got this right, I turned the allen bolt on the regulator counter-clockwise causing the speed to increased.
Does that mean that I "closed" the regulator? Is that what you meant?
 
FINAL SETUP: 3/8 turn "counter-clockwise" on the regulator and the hammer spring adjusted out to 890 FPS.

Here are the final results - 84 shots with an average speed of 894 fps and an extreme spread of only 11 fps.

Not sure I can do any better than this. Check the average speeds on the photos beside every magazine of 14 shots.

Thanks for all the help.

Have a good evening,
Miguel.

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