[ghilliegan]

I bought a used sniper rifle and I am still getting acquainted with it. I have an issue with the weight of my bb and the hop up.

Here is a list of the parts in it:
-Maruzen Type 96
-PDI 240 Spring
-Laylax Spring Guide
-Laylax High Pressure Piston
-Laylax Teflon Cylinder
-Laylax Zero Trigger
-Prometheus PSG-1 650mm 6.03 Tight Bore Barrel
-Pro-Arms 6.5inch Silencer / silencer attachment
-PDI Hop Up Chamber
-Laylax APS2 and L96 Power Accuracy Cup

When I first started shooting the rifle, I was using .3 grams bbs and I noticed NO hop-up on the bb at all. The shots were consistent and straight but I was only getting about 160 feet for range. I started to adjust the hop up but apparently I needed high arms for the PDI chamber. I installed the high arms and went to test it with four different weight of bbs. I used .2, .25, .3, and .43 and I was shooting a tree that was 180 feet out with little to no wind.


The .2 gram bbs had EXTREME hop up and range but no consistency. (220ish feet then I lost the bb)

The .25 gram bbs had the best overall combination of range and accuracy. I was getting shots out to 180 feet fairly accurate but there were still quite a few inconsistent shots that would hang right just before the target tree. The hop up on the bb was good but I think that I need a heavier bbs to help reduce the impact of wind affecting it.

The .3 gram bbs shot very consistent and straight but I am only getting about 170-180 feet for range now. I am noticing minimal hop up on the bb.

The .43 gram bbs shot consistent and straight but I am only getting about 150-165 feet of range. Absolutely no hop up on the bb.

Any suggestions or experience with this type of issue? My goal is to get accurate shots out to at least 200 feet. I do not think that is unrealistic. Thanks in advance.

 

[Cheese Man]

Firstly, clean the hop up unit inside and out, and grease everything. Next, wipe all the grease off the inside of the hop chamber. Then, clean your bucking as per my guide (linked in my sig). Then, if that doesn't work, get a shorter barrel, the stock length is 495 mm. Much longer than that and you may be needing a bore up kit.

.3 is just about right for around 550 fps and a PDI hop chamber. I used .32s in mine...

 

[hoggie]

First off, you have the exact same parts as my gun basicaly, and i'm getting way farther out then 200 with a .43. First, make sure you are adjusting them the ring way. Clean your bucking, barrel, and gun. If all else fails, it's the barrel length.

 

[fuzzywolly]

I had a similar set up, only I was using .4 gram bbs, and a SP 130 spring. Put my FPS at about 400 or so. You should be able to carry the heavier bbs, and I could even adjust the setting to carry them almost straight up with a ridiculous amount of hop. I assume you cannot get your heavier bbs to get this kind of hop?

What bucking and nub are you using? Perhaps you are using a hard, which could be the cause of this.

 

[ghilliegan]

I am not exactly sure what the brand the nubbin and bucking are but I am fairly certain it is a soft bucking. I never handled a hard type so I have to assume. I looked at some pictures of hard and soft buckings and the bucking is a squishy piece of rubber so I am confident that I have a soft. Also, the nubbin is a clear cylinder shaped piece. Is there a default nubbin that comes with the PDI Chamber? I would think that it would be that one if so. I chrono'ed my rifle with .2 gram bbs not to long ago and it was shooting 475 FPS, forgot to mention that...

I will check out your guide a bit later after work but I am not exactly sure what you mean by grease the chamber. Silicon or the white lithium that you swear by? If your guide explains it, no need to answer it. Thanks for the help.

 

[fuzzywolly]

Sounds like you are using a PDI nubbin, the stock nubbin that comes with the chamber, one of my favorites.

I would check the bucking, inspecting it for anything deformed, ripped, etc. That is the first thing you should check.

 

[Cheese Man]

My guide doesn't explain the hop up chamber. What I do, is to wipe it out with a rag, until I can't feel any grease on the inside (white lithium grease ), then, I apply my favorite grease to the inside of the chamber. You have to make sure the chamber is empty first. Then, use your clean bucking, apply a VERY thin coat of the same grease to the OUTSIDE ONLY of the bucking, and out it all back together. Make sure to grease the hop arms too, that can cause issues.

 

[awagg]

I would recommend using the PDI bucking, with the PDI chamber. It's made for it, and my increase your range. It's definitely worth a try.

 

[ghilliegan]

Alright, here is the update.

I took everything apart again and -closely- inspected it for any rips, tears, abnormalities, etc but everything seemed legit. I put it back together and took some test shots. I actually measured my target tree and it is 190 feet away. There was a clothes line hung from this tree so I used the metal screw piece as my point of reference to shoot. I began shooting and it was no different from before but I continued to adjust my hop up (a million times it felt like) and I started to see some hop up on my .3 gram bbs. It was weird because I was getting inconsistent hop up on the bb. One shot would have AMAZING backspin and then the next would be as before, no backspin dropping 10-20 feet before the tree. I kept shooting and I noticed more shots were achieving the amazing backspin and accuracy but I still had some poor shots as well. My brother started shooting with me and told me to try and achieve the same shot everytime. This included the point of reference (mentioned earlier), breathing, and the trigger pull (which I did not consider). Oddly enough, the trigger pull seemed to be more important than I realized...maybe. I was using a light pull on the trigger in most my shots then I switched to a stronger more full trigger pull than before. Call me crazy, but I noticed more consistency in the hop up of the bb than the lighter pull. The only rational thought that I could come up with was that it released the spring differently between the two pulls. I ended up running out of day light but by the end of the day, I achieved a full magazine worth of bbs with amazing hop-up smacking my target tree with accruacy. The bbs still had more range to it but I did not have the distance to see how far it could reach out. More testing to come but this is what I noticed after 100-125 shots.

I want to say thanks to everyone for taking the time to share some knowledge with me. I will continue to test and let you know what I come up with.

 

[Cheese Man]

Did you put loctite or teflon tape on grub screws that adjust the hop arms? That may be an issue in the future, or right now, so I would try that.

 

[ghilliegan]

Interesting, no I did not but that seems like a good idea if I continue to experience the same issue with inconsistent hop up. Thanks.

 

[ryan]

I was having this issue with my PDI chamber in my VSR-10. I had the adjustment screws almost all the way out but the hop up would not go down past halfway through their range of adjustment. It turned out that the o-ring that holds the arms down had stretched from being removed numerous times for hop up cleanings and was not putting enough force to squeeze the bucking down through the barrel. I replaced the o-ring with a thin rubber band which I wrapped several times and voila tons of hop again. Sounds like you may have it figured out, but it's probably worth checking.