Do mini cockers need volumizers

[Psycho91]

Building a mini cocker and want to know if I should run a volumizer or not

[Jonnydread]

Short answer, no. Long answer, depends on what you're trying to get for performance. They're not necessary.

[Grendel]

I was getting ready to type essentially the same thing. Great minds (or demented) think alike

[Psycho91]

Well then ok lol

[Psycho91]

If I was planning on sending it to cocker top to get his butter mods done would it help, even if it's just a tad, I mean I got enough in it already

[superman]

I typically do recommend using a volumizer on a mini cocker, especially the trilogy we were talking about with the spacer.

cocker top is drilling the valve face to nearly the same size as the valve stem and then changing the springs. That is all the butter mod is. The reason it has become popular is because people think they need it, but don't really understand what it is or does. Some cockers actually like running at higher pressures, be it the regulator, the springing etc. The problem is people end up getting their cockers back and don't understand how the changes effect the velocity or how to keep it shooting the way it was when it was returned. I know of multiple markers that have been sent to techs after buttermodding to then only have the valve that was installed swapped with the stock valve because it shot just fine.

Other techs docfire, angry antle have done some testing to actually show that the same pressure can be achieved on a pretty much stock shocktech lowertube kit. Which is a drop in kit that does not require you, paying shipping both ways and waiting in line for someone to drill and polish a valve face. Several videos on youtube with cockers shooting sub 300psi on stock shocktech lowers.

That being said if you want the valve drilled out, i would be happy to do it. you want me to polish it, I would be happy to do it. hell i bet i could turn it around the next day even.

[Cdn_Cuda]

Thanks superman for explaining what the butter mod is. Have seen it referenced on facebook a few times now and had no idea.

[superman]

your not missing anything there. you will see it mentioned alot of times in the sale listings. It often makes me wonder if the users are having issues keeping the markers running and decide to sell it for something else. That is likely more speculation than anything though.

[warbosschoppa]

Some Pre2k bodies don't have the volume and isn't a bad idea to put it on just in case. AKA has some cheap Miteymax Pre2k volumizers on their site.

[Spider!]

Also, the top of the hpr can help the same way as a volumizer. If your vert reg adapter has adequate porting, the volume in the top of the reg is effectively part of the dump chamber. Some regs have more space above the piston than others.

[Psycho91]

Hmm I never would have thought of that

[superman]

I agree with this also. Regs like Cp, sidewinders tend to be better than regs like ccm, bob long etc.

[RuleOfSines]

I like em aesthetically, but they sure as heck make working on the front end a hassle.

[latches109]

Also, the top of the hpr can help the same way as a volumizer. If your vert reg adapter has adequate porting, the volume in the top of the reg is effectively part of the dump chamber. Some regs have more space above the piston than others.

this is important^^, and is why a long AKA reg is beneficial -extra volume for higher ROF. The reg needs to keep up with whatever pressure you want to shoot. Reg keeping up means there is little to no pressure drop shot to shot. Minicockers have very small dump chambers and need to be run at higher pressures -> Higher pressures mean stiffer springs. If you go low pressure with light springs your velocity might be too low or your shot to shot FPS will fluctuate. Running the higher pressure and stiffer springs will provided better consistency. The volumizer (banjo or reg) will help with consistency if you are going the low pressure route.

applies to minicockers.

[latches109]

Left - to - right

pre-2k bajno
2k banjo
merlin banjo - 2k valve chamber
merlin banjo - pre-2k valve chamber ( pre 97 is even smaller )

think of it this way. the larger volume allows the air to travel less distance(time)
Springs, hammer weight & size, pressure, flow, all affect your dwell time.
tricky part is getting the balance right.
increasing pressure reduces dwell time, increase too much and the pressure holds the valve closed by pushing on the valve stem.


Let's say you increase pressure, result -FPS increase, you keep doing this until the FPS drop. This is the inflection point for combination of parts you are tuning. At this point, the dwell time reduction is equal to the air flowing out. beyond this point the dwell time will reduce the air flowing out and lower FPS. This is the confusing part for most people when tuning autocockers.

The pink body with the pre-2k valve shoots at ~240psi, the body to the left of it with same exact internals and springs, and IVG setting (used a rex dialer for consistency in the setting) shoots ~30psi lower.
Why, because it needs more air from further up the valve chamber and reg - more travel time - increase the speed of air flowing out.