After reading and reading I think I have figured out that the adjustable power spring and the adjustable hammer are the same thing. I think I have it figured out that the reason to have one is to turn the power down to get more shots per CO2 cartridge for plinking fun and up for serious shooting. Is this correct?
If I don't care about maximizing shots per cartridge, is there any reason to invest in an adjustable hammer on a 2240?
Thanks,
-AJ
I think the power adjuster (PA) or pressure adjuster assembly in the Crosman line was intended to allow the user to relieve hammer spring tension so you could get more shots per cartridge. If the hammer hits the valve stem with less momentum, the valve closes off sooner and less CO2 is used to propel the pellet. This effect also reduces pellet velocity. A side product of an adjuster is the ability to increase velocity when certain spring/hammer combinations are used.
PAs look tough on a pistol. Bling folks like that. PAs may minimally increase velocity or may show no change over the entire travel of the PA. The key to the velocity thing is having the right hammer spring, and even then, I never experienced any significant gains in pellet velocities. Most of the time I set my PA to one setting and never move it.
The smart guys will be along soon to clarify this.
Quote from: breakfastchef on January 30, 2013, 03:18:38 PM
I never experienced any significant gains in pellet velocities. Most of the time I set my PA to one setting and never move it.
I've really wanted to believe they would help but alas, I have had the same experiences as breakfastchef. While they do look 'kool' that is about all you will get.
Now others are going to disagree but that is true with many things in airgun adventures. And of course, your own mileage may vary.
Carl
Same here, I have given up on them altogether. I have never seen the point or benefit to be honest other than they add a bit of trim to the back.
They are outright dangerous in the UK though, loads af guys think they can ramp up their rattys and turn them down via the PA thinking it is ok with the law. When all the law will do is turn them up and land them in the poop !
A ha! I am getting it then.
So the stronger hammer springs I see for 2240s, is that basically the same thing without the ease of a knob for adjustment? You have to swap springs back and forth if you want to change velocities?
Thanks again,
-AJ
Quote from: ajhuff on January 30, 2013, 04:34:01 PM
A ha! I am getting it then.
So the stronger hammer springs I see for 2240s, is that basically the same thing without the ease of a knob for adjustment? You have to swap springs back and forth if you want to change velocities?
Thanks again,
-AJ
Well in the UK the standard pistol is 5.5 ft lb so it is close to the legal limit anyway so we shouldn't be changing them over here.
So yes the PAs are good for that if you want to flip the springs out I suppose.
That said I tend not to change the springs anyway in any of my guns I just keep them standard.
;) I have built such a hammer for my regulated m-rod rifle.
Rather than the factory travel screw which INCREASES spring pre-load as Travel is reduced .... my design keeps spring pre-load EXACTLY the same but allows Stroke Increase or Decrease.
Spring pre-load remains independent from OEM adjuster.
WHY ??? .... Can tune power with light pellets at 12# limit or anywhere in between to a Max of 35# power levels with MAXIMUM EFFICIENCY across the spectrum of .177 & .22 pellet weights.
Quote from: Motorhead on January 30, 2013, 05:37:21 PM
;) I have built such a hammer for my regulated m-rod rifle.
So this hammer adjusts similarly to a 1701P hammer in that the striker can be adjusted while the hammer spring remains unaffected?
Quote from: Motorhead on January 30, 2013, 05:37:21 PM
;) I have built such a hammer for my regulated m-rod rifle.
Yep, I do remember reading about this adventure on the GTA if I remember correctly.
Carl
Quote from: quickster47 on January 30, 2013, 07:58:00 PM
Yep, I do remember reading about this adventure on the GTA if I remember correctly.
Carl
Is this what you mean Carl?
http://www.gatewaytoairguns.org/GTA/index.php/topic,39387.0/topicseen.html (http://www.gatewaytoairguns.org/GTA/index.php/topic,39387.0/topicseen.html)
I read this 4 times and still only understand half ???
Motorhead and rsterne have pretty clever way to adjust hammer energy and momentum
and they can tune with these contraptions to get the ME they want - amazing stuff good job Motorhead :-*
Thanks guys. I think you all just saved me from temptation. Doesn't sound like I have any need to change my velocity. I am fine with my shots per cartridge. So think the stock hammer and spring is perfecly adequate for my needs.
Thanks again!
-AJ
Quote from: WyoMan on January 30, 2013, 08:27:57 PM
Is this what you mean Carl?
http://www.gatewaytoairguns.org/GTA/index.php/topic,39387.0/topicseen.html (http://www.gatewaytoairguns.org/GTA/index.php/topic,39387.0/topicseen.html)
I read this 4 times and still only understand half ???
Motorhead and rsterne have pretty clever way to adjust hammer energy and momentum
and they can tune with these contraptions to get the ME they want - amazing stuff good job Motorhead :-*
That would be it. Very good stuff and not too terribly difficult to follow as long as you have time to read slowly. :)
Carl
Thanks guys ... These dang AG's and all the little gadgets and doodads one can fabricate is dang near endless :-*
Success or Failure you just never know till you try ... Yup experience gained either way it turns out ;)
I got this from the Crosman site about the 2300S which has a PA
Adjustable hammer spring lets velocity be adjusted to between 440 to 520 feet per second
so it looks like it does change how fast the gun will shoot thats a 80 fps difference hope this helps out some
Jim
Quote from: brz-ryder on January 31, 2013, 10:13:49 AM
I got this from the Crosman site about the 2300S which has a PA
Adjustable hammer spring lets velocity be adjusted to between 440 to 520 feet per second
so it looks like it does change how fast the gun will shoot thats a 80 fps difference hope this helps out some
Jim
I quite often take this kind of information with a great big grain of salt. Especially when you consider how most manufacturers advertise the FPS a gun shoots.
Carl
After reading many posts on adj hammer spring devices, I want to try one out. I would use it to reduce fps for good target shooting/plinking, while increasing # of shots per cart. When the opportunity arose to do some varmint reduction, I can increase fps for knock down power. Sighting for the lower fps, then seeing what hold was needed on high fps. Has anyone done this, and how does it work for you?
i have one PA that i use to finetune my guns. when i am happy with the fps, accuracy and shot count, it is all a juggling act compromising one to acheive the other. i then remove the PA and install a new cap with a spring guide machined to the same size(spring preload)as the PA. works just fine.
Quote from: cheewee on February 02, 2013, 07:05:53 PM
i have one PA that i use to finetune my guns. when i am happy with the fps, accuracy and shot count, it is all a juggling act compromising one to acheive the other. i then remove the PA and install a new cap with a spring guide machined to the same size(spring preload)as the PA. works just fine.
Good idea! :-*
Well all i know is with the PA out i get 20 to 25 full power shots with it screwed in i get 12 to 15 wheres the CO2 going if not pushing the pellet faster. Most of what rsterne talks about is pcp guns i don`t know if that applys to CO2 guns i`m new to the sport
Jim
Quote from: brz-ryder on February 03, 2013, 02:40:47 AM
Well all i know is with the PA out i get 20 to 25 full power shots with it screwed in i get 12 to 15 wheres the CO2 going if not pushing the pellet faster. Most of what rsterne talks about is pcp guns i don`t know if that applys to CO2 guns i`m new to the sport
Hammer bounce is likely the short answer to your question.
The hammer hits the valve stem and releases CO2, which in turn propels the pellet. When the CO2 rushing into the valve from the powerlet creates enough pressure, the valve spring closes the exhaust port sending the valve stem back into the hammer. The hammer is pushed backwards and bounces off the hammer spring and rebounds to hit the valve stem again, but with much less force. This rebounding causes CO2 to be lost out the exhaust port after the pellet has long left the barrel. This whole rebounding process takes place very quickly. Hammer debounce devices (HDDs) are made to reduce or eliminate hammer rebound in order to increase shot count by not wasting CO2.
x2 wasted co2
there is a point at which at a fixed pressure (950psi) adding extra volume will not give an increase in fps but only waste co2.
I was reading some about those HDD's anyone using them? can you actually tell any difference?
Depending on the barrel length, releasing more co2 per shot does not necessarily mean it all goes to higher fps. If the pellet leaves the barrel before the volume of co2 has propelled it to it's highest fps , some is wasted. Longer barrels benefit most from higher volumes of co2 expulsion. I have read that somewhere around 18" is optimal barrel length for these modded pistols.
Quote from: blake.l on February 03, 2013, 05:12:09 AM
I was reading some about those HDD's anyone using them? can you actually tell any difference?
I have used HDDs off and on. Several of my target shooting guns have them and they appear to work. How well is quite subjective. In theory there application makes a lot of good sense but the problem is making one that works reliably and good. Steve in CT, his handle on the Green and Yellow forums, probably makes the best one but they are expensive for what you are getting. arkmaker tried his hand at making some and his did okay too. There was another design that used o-rings and sort of looked like a backward pellet. And basically what they are doing is applying friction to the hammer after the initial shot to slow the bouncing of the hammer against the valve stem.
Carl
Here are a couple of pictures of the two different HDDs I've been using as of late.
The all white one is from Airguns of Arizona, designed by Steve, and the other is by a fellow that I cannot remember his name.
Carl
Quote from: quickster47 on February 03, 2013, 11:02:09 PM
and the other is by a fellow that I cannot remember his name.
Steve McCann. His HDD seemed like a good idea but was far from 'prime time'.
Quote from: breakfastchef on February 04, 2013, 01:07:10 AM
Steve McCann. His HDD seemed like a good idea but was far from 'prime time'.
Thanks Chef. :)
I also thought he made a second version but never have heard from him again. Guess I should send him an eMail and check it out.
But you are correct, the results of using his was very lacking.
Carl
Quote from: breakfastchef on February 04, 2013, 01:07:10 AM
Steve McCann. His HDD seemed like a good idea but was far from 'prime time'.
I made a bunch of these with all different angles and tried a half dozen materials for both pieces. Never could get it to work consistently. I believe the part is just to short to allow for the proper angle. My take anyways. When I was approached to make them, my first thought was that we may have a winner. Alas, it was not to be.
I wonder if one like used on the qb rifles could be fashioned to work?
Quote from: arkmaker on February 04, 2013, 11:45:01 AM
I wonder if one like used on the qb rifles could be fashioned to work?
Now there is a good though Rich. May have to try something like that. But alas, like you, it is way down there on my priority list.
Carl