Regulator question

[Jfrench]

Will I need to adjust my hammer spring on at44 when I get my regulator installed ?  Or will the regulator be all i need to adjust ?   And any idea what setting to be around 900 fps

[Hobbyman2007]

You will need to tune to whatever you set your regulator pressure at. Search tuning a regulated pcp .lots of good reading . I follow Bob Sterne's method .

[Rallyshark]

There are a few variables to consider here.  What pellets, have you modded the gun, do you plan on changing the power level often, etc..  The short answer is yes, if you set your reg to the right bar.  I personally have my reg set a little higher than it needs to be for the fps I shoot.  I have my spring at minimum, but I can give it a couple of turns and pick up 75-100fps if need be.  Another advantage to setting the reg to a higher bar than you need for a given fps is efficiency.  If the gun will shoot what you want  at say 115 bar, then set the reg for 120-125 bar.  That way the extra pressure closes the valve faster and doesn't waste as much air.  Also, when it isn't wasting air, it is much quieter   Sometimes, you will get more shots with reg set slightly higher, than you will with it set at the minimum to achieve your desired fps too(efficiency).  That is how my regulated cylinder is set up, and it works very well for me. 

I don't mean to make it sound more complicated than it is.  Like I said, the short answer is yes,lol!  Tell us what fps you want to shoot with a given pellet, if the guns is modded(if so how), and we can give you a good ball park to set the reg at.  We'll also need to know the specific gun(AT-44 short or long etc.).  What Denis said can be quite useful as well!

[Jfrench]

I'm happy with the accuracy of the aa field heavys.  18 gn
But I'll have to shoot thew chrono tonite to see what speed I'm at now .  haven't checked any of that since I put the new valve in Saturday . but I think I'd like to be shooting around 900 fps .  tracking says regulator exspected to be here 4/13 .
So I got time to do mods to my gun I you think I should ?
Its stock,  at 44 long qe

[Rallyshark]

In my opinion, modding the AT-44 is a no brainer if you have the means to do it.  If done right you will most certainly gain efficiency, and you can also gain power if you want.  I followed the post Bob(rsterne) did to the letter, and I had a pretty big improvement with no negative effects.  Here is the thread if you need it : http://www.gatewaytoairguns.org/GTA/index.php?topic=33903.20  Just keep in mind this was a .25, so adjust accordingly for .22.

The only thing I didn't do was drill the holes in the valve face on my regulated cylinder, since I didn't really need to get all the power possible.  I think in my non-regulated cylinder drilling the valve face made about 15-20 fps difference, but I don't remember for sure.  In my regulated cylinder, I think the rest of the mods gained me about 10 more shots, and allowed me to set the regulator at a lower bar and achieve the same fps.  I'm just going by memory, but I think I got about 27 shots regulated at 134 bar shooting JSB 18.1gr. at 915fps before modding it.  After modding it, I was getting 35+shots with the same fps, and the reg set to 124 bar.  So, that is a pretty big improvement! 

Now, I have added a hammer buffer, and dropped my fps a little, and I get about 50 shots at 855 fps with the H&N 19.09gr. BCHE pellets, and the reg set at 120 bar.  My gun can shoot about 915-920fps(19.09gr.) at that reg setting if I want, but it isn't as efficient.  That is a little better than average, which is partly due to the buffer, and a stretched valve spring, but lets not get ahead of ourselves to start with   I would go with the valve mod(including the valve seat), and doing the barrel and transfer ports.  I think for the .22, you'll want to go with a 11/64 size hole/ports, and smooth them up.  This is all assuming you are comfortable doing these mods yourself.   If you aren't, we can recommend someone to send it to and have them do it.  I hope this isn't information overload.  It will all make more sense after you read through Bob's post he did on his .25.  I will tell you that once you get it tuned right, it is REALLY quiet! 

The mods will make the gun work better without a regulator as well, which is why I ordered a second short cylinder and basically went nuts on it just to see how much I could get out of it,lol!  I was able to get the unregulated cylinder to shoot the 25.39 JSB .22s as high as 991fps, but with way less shots of course. 

The short version is:  If you don't mod the gun, you'll need to set the regulator around 130-134 bar to get the 18gr. pellets shooting around 900fps.  If you mod it, and get it right, you'll be able to set the regulator around 115-120 bar and achieve your desired fps and a few extra shots.  That's all I got for now!

[BigTinBoat]

Now, I have added a hammer buffer, and dropped my fps a little, and I get about 50 shots at 855 fps with the H&N 19.09gr. BCHE pellets, and the reg set at 120 bar. 

What did you use for the "buffer"? any pics?

[Rallyshark]

Now, I have added a hammer buffer, and dropped my fps a little, and I get about 50 shots at 855 fps with the H&N 19.09gr. BCHE pellets, and the reg set at 120 bar. 

What did you use for the "buffer"? any pics?

Sorry, I don't have any pictures, but this is what I used as a buffer:  http://www.losi.com/Products/Features.aspx?ProdID=LOSA9315

It is just rc car fuel tubing that is placed in between the hammer and brass fitting that the cylinder screws into.  This particular one I posted the link to is slightly larger in diameter than some.  It is 1/10-1/8 scale nitro rc car fuel line.  The one I used is a piece that is about 2.25" long.  It doesn't wrap all the way around the trigger tube, so there is a gap between the ends to allow for the hammer stop screw.  It is silicon, and stays in place, since it really has nowhere to go, and the hammer firing will make sure it is always in the right spot.  If you use some that may be slightly smaller in diameter you may need a piece that is about 2.5" long.  It really made a difference in my gun.  If the gun is dry fired, the hammer barely hits the stop screw if at all.  Does that make sense?  I'm told it is similar to a bstaley mod?  I think it is better, since it has more give, but is thicker and allows more movement at first.  I gotta hit the sack, but I can make a diagram tomorrow if you need me to.  It literally wraps around the wall of the trigger tube, and sits between the hammer and brass fitting that the cylinder screws into though.  I hope I making sense?

[Jfrench]

Thanks shark .
Oh and 50 shots at 850 would make me very happy lol !!!

[BigTinBoat]

It is just rc car fuel tubing that is placed in between the hammer and brass fitting that the cylinder screws into.  This particular one I posted the link to is slightly larger in diameter than some.  It is 1/10-1/8 scale nitro rc car fuel line.  The one I used is a piece that is about 2.25" long.  It doesn't wrap all the way around the trigger tube, so there is a gap between the ends to allow for the hammer stop screw.  It is silicon, and stays in place, since it really has nowhere to go, and the hammer firing will make sure it is always in the right spot.  If you use some that may be slightly smaller in diameter you may need a piece that is about 2.5" long.  It really made a difference in my gun.  If the gun is dry fired, the hammer barely hits the stop screw if at all.  Does that make sense?  I'm told it is similar to a bstaley mod?  I think it is better, since it has more give, but is thicker and allows more movement at first.  I gotta hit the sack, but I can make a diagram tomorrow if you need me to.  It literally wraps around the wall of the trigger tube, and sits between the hammer and brass fitting that the cylinder screws into though.  I hope I making sense?

Makes perfect sense. It would be kinda hard to do the BSB with that screw stop. This looks lie a good alternative.

[Rallyshark]

Thanks shark .
Oh and 50 shots at 850 would make me very happy lol !!!

Keep in mind, it took me a lot of tinkering to find that sweet spot of pre-load/buffer/reg setting.  I actually placed a spacer between my hammer spring and hammer.  I did that so that it would be where I wanted with the pre-load at minimum.  I would imagine on a normal gun that my pre-load would be equivalent to around 2 turns out.  Also, I do fill my gun to 3000 psi, and not 2900.  I just want to make sure I'm telling the whole story   But yeah, the AT-44 is ripe for a little "tuning".  It makes so much difference, and the regulator is just icing on the cake.  If you mod the gun in combination with the reg, you're going to have one fine shooting tool.

It is just rc car fuel tubing that is placed in between the hammer and brass fitting that the cylinder screws into.  This particular one I posted the link to is slightly larger in diameter than some.  It is 1/10-1/8 scale nitro rc car fuel line.  The one I used is a piece that is about 2.25" long.  It doesn't wrap all the way around the trigger tube, so there is a gap between the ends to allow for the hammer stop screw.  It is silicon, and stays in place, since it really has nowhere to go, and the hammer firing will make sure it is always in the right spot.  If you use some that may be slightly smaller in diameter you may need a piece that is about 2.5" long.  It really made a difference in my gun.  If the gun is dry fired, the hammer barely hits the stop screw if at all.  Does that make sense?  I'm told it is similar to a bstaley mod?  I think it is better, since it has more give, but is thicker and allows more movement at first.  I gotta hit the sack, but I can make a diagram tomorrow if you need me to.  It literally wraps around the wall of the trigger tube, and sits between the hammer and brass fitting that the cylinder screws into though.  I hope I making sense?

Makes perfect sense. It would be kinda hard to do the BSB with that screw stop. This looks lie a good alternative.

That was my thought on it, and I wanted to leave the stop screw in place.  The good thing about the tubing, is that the diameter is just small enough to allow the center of the hammer to pass through the "loop" of tubing.  This also helps it absorb the hammer shock a bit better, since it basically fills the space between the center of the hammer and the trigger tube.  With it being silicon, it won't deteriorate, and no chemicals are likely to harm it.  Best of all it isn't expensive, and relatively easy to install.  You may have to increase pre-load slightly to get the same fps you would have otherwise, but that means you're hitting that valve with the minimum amount of energy needed, and less wasted air.  My gun is SO QUIET now, even when I shoot the unregulated cylinder at 45-50 fpe.  When I first did this, I wasn't aware of the BSB, and I was telling Bob.  He says "so you did a BSB on it?"  He just popped that balloon, haha.  You can get the tubing from any hobby store that does rc cars, or order it online.  You can even get a couple of different kinds that have slightly different outer diameter to play with.  I used the Losi tubing, since it was the largest outer diameter I thought would work.  If you try it, I would love to hear how/if it worked in your case!  As far as I know, I haven't heard of anyone else doing this specifically or their results if they have.  I would just like to have my results duplicated on another gun etc.

[BigTinBoat]

  If you try it, I would love to hear how/if it worked in your case!  As far as I know, I haven't heard of anyone else doing this specifically or their results if they have.  I would just like to have my results duplicated on another gun etc.

Just ordered some this afternoon. In addition to my .177 I just picked up a .25 will try it in both.

What did you set your reg at for the .22 to get 35FPE? This one came with a reg in it, just need to fill the valve holes and tune it. In fact I got 2 cylinders with the gun, a long and a short. Thinking of leaving the reg in the long cylinder and removing the reg from the short and use it for high power. Would be nice to use min preload with the reg'd cylinder to get max shot count at like 35-40fpe and then be able to just crank up the spring, switch the cylinder and get 60-70FPE for a mag.

[Rallyshark]

  If you try it, I would love to hear how/if it worked in your case!  As far as I know, I haven't heard of anyone else doing this specifically or their results if they have.  I would just like to have my results duplicated on another gun etc.

Just ordered some this afternoon. In addition to my .177 I just picked up a .25 will try it in both.

What did you set your reg at for the .22 to get 35FPE? This one came with a reg in it, just need to fill the valve holes and tune it. In fact I got 2 cylinders with the gun, a long and a short. Thinking of leaving the reg in the long cylinder and removing the reg from the short and use it for high power. Would be nice to use min preload with the reg'd cylinder to get max shot count at like 35-40fpe and then be able to just crank up the spring, switch the cylinder and get 60-70FPE for a mag.

Awesome, I can't wait to see if you get good results with it!  My .22 can do 35fpe with the reg where it is(120bar) if I give the spring a turn or two.  It would probably be a little more efficient shooting 35fpe with the reg set at 124 bar though.  You're thinking exactly how I was with two cylinders.  I got my additional(short) cylinder to set it up for max power for just a few shots.  I have the regulated long cylinder for most shooting, and my short non-regged one in case I want to take on something that may need a bit more juice.  As a matter of fact, I just used my short cylinder for a beaver problem the other night:)  So, it did exactly what I wanted it for.  Like you're thinking, all I have to do is change to the short cylinder and give the spring 5-7 turns, and I have about 20 extra fpe at my disposal.  With a .25, you should be able to get it up over 60fpe no problem.  I think Bob managed to get his up to 78fpe with his .25.  Also, with your .25 you can follow Bob's post to a T!  With my .22 the usable peak is around 55fpe, since I can't fit any pellet more than 25.39 grains in my magazine.  Still, that ain't bad for a .22. 

[Jfrench]

I took a chainsaw file and did the stock mod , drilled the 1/8 in hole behind mounting bolt also.
Makes it way easier to adjust for sure.
Going to look for screws tonite and do the valve mod .
What size do I want ?
6/32 ,   4/40 ,   or 11/64 ?   I keep seeing different sizes in differant posts

[BigTinBoat]

Awesome, I can't wait to see if you get good results with it!  My .22 can do 35fpe with the reg where it is(120bar) if I give the spring a turn or two.

Great. This one is a Huma and the dial is sitting right on 124 now.

I took a chainsaw file and did the stock mod , drilled the 1/8 in hole behind mounting bolt also.
Makes it way easier to adjust for sure.
Going to look for screws tonite and do the valve mod .
What size do I want ?
6/32 ,   4/40 ,   or 11/64 ?   I keep seeing different sizes in differant posts

I used 6-32 in my .177

[Jfrench]

I plugged 4 of the 6 holes . didn't have one line up, and drilled valve seat out am now waiting for jb weld to dry . tracking also says my regulator is in N.Y. as of last nite
Only thing I don't look forward to is pumping the cylinder up from zero again .  And then again when my regulator comes in .... Lol. 

[BigTinBoat]

I plugged 4 of the 6 holes . didn't have one line up, and drilled valve seat out am now waiting for jb weld to dry . tracking also says my regulator is in N.Y. as of last nite
Only thing I don't look forward to is pumping the cylinder up from zero again .  And then again when my regulator comes in .... Lol.

I used to be the same way.......then......

[Jfrench]

I'd run over and have you fill it for me but your 12 or 13 hrs away .     lol

[Rallyshark]

I plugged 4 of the 6 holes . didn't have one line up, and drilled valve seat out am now waiting for jb weld to dry . tracking also says my regulator is in N.Y. as of last nite
Only thing I don't look forward to is pumping the cylinder up from zero again .  And then again when my regulator comes in .... Lol.

Mine didn't line up either, so I varied it a bit.  You could also order some brass shims from mcmaster carr I think.  I ended up plugging 5 holes, but making another hole to the side of the 6th hole, and merging the new hole with the existing one.  I just didn't drill out the holes as large as I would have otherwise.   I drilled them at an angle so they are pointing slightly towards each other.  The thin bit of brass between the two holes sits dead center with the transfer port.  The hole lined up on my non-regulated cylinder though.  Anyway, here's a picture of what I did with mine(before I cleaned up the edges), since I didn't want to shim it or machine it down to line up.

[Jfrench]

I didn't open mine up as much as you did ,
I'll see what I get and maybe open them more ?
Thanks for helping me with this

[Rallyshark]

I didn't open mine up as much as you did ,
I'll see what I get and maybe open them more ?
Thanks for helping me with this

You can always open them up more, or plug that 5th hole and do like I did.  I saw your stings you posted, and it looks like you're going to need to open them up more your way or mine, but more.  Also, if you didn't do the barrel and transfer ports, you need to get on that.  I actually used rolled up sand paper to do my transfer, since it would be really easy to mangle it trying to drill it out.  I started with 220, and then went to 400 to smooth it out more.  I did my transfer to where the shank of the 11/64 bit would fit through it fairly easily, but not too easily.  After you do the barrel port, make sure to take the rolled up sand paper to the inside of the barrel port to smooth it out.  You don't want any burrs catching the pellets when they are loaded.  Actually, you could use the diamond ball to smooth out the edges of the barrel port if you prefer.  Oh, and I used the rolled up sand paper on the valve seat too, and to the point that the 11/64 bit fits through it pretty easily.  I know the 11/64 bit didn't really make the seat much larger, which is why I got on it with the sand paper too.  I hope that helps