Bushmaster Breaking Paint: Fixes

[Myrkul]

Well, I FINALLY managed to get my old bushmaster (Serial# 1417) shooting the way it's supposed to with modern paint (D3fy, approximately 0.682). There was a lot of trial and error that went into this so I figured I'd pass along what ended up working for me in case anyone else has the same issues with their bushy always breaking paint.

Step one:
The old tried and true polished Ram Shaft & Autococker Valve spring. I went with an SLPS autococker valve spring on this on and it is LIGHT. Polished up the ram shaft as well. This makes the gun smoother and enables you to drop the LPR pressure.

Step two:
Drop a #011 "O" ring in the back of the ram. This causes the bolt to sit further forward in the breech, and helps compensate for small modern paint.


Step three:
Modify the bolt by ripping off Planet Eclipse's cure bolt design. I tried a few different styles, and a 5 degree ramp on the top edge of the bolt seemed to work best. I went with Vapor bolts to minimize blowback up the feed neck and improve the velocity more, (which in turn lets me set the LPR even lower). Special thanks to the member here who made the cuts for me.


Step four (optional):
A lot of the later model bushies came with dual "o" ring style detents. This one did not, single autococker style detents. I was getting double feeds with a single detent, so I'd recommend adding the second one if its not already there. I did drop down the BPS to 10.5 and turned off ramping on the Chaos board as well, didn't want to press my luck too hard with this tiny paint.

And that's it. Made it through approximately 1,400 paintballs this weekend and didn't have a single chop, barrel break, or stack clip. Nostalgia hit me right in the feels ripping it up with this monster again. Just wish there were some angel owners playing that day so I could make them feel bad all over again...but you know proprietary batteries & time...

[BrickHaus]

Cue jack wood to come atchya like cleopatra.

Lmao, awesome work buddy!

[Myrkul]

They aren't complicated at all, anyone with even halfway decent soldering skills can do it, I'm just bad at electrical. The boards always hold up just fine, and the old Skinner solenoids last for freaking ever. Just crappy old wires, easy fix in most cases.

[BrickHaus]

Well, send me some pics yo. Ill fix em for ya.

[Myrkul]

Is this helpful?

[OpusX]

It is an odd beast, but certainly a beast. Shot great for the game I played with it. Who would have thought that simple angle cut makes all the difference.

[Myrkul]

You got that right, the Y-Frame feels so wrong, but at the same time so so so right.

[glaman5266]

I see you have a Rotor on there. Have you tried an agitated or semi-force feed on it? I'm sure an Egg 3 or Egg 2 cranked up would feed fast enough. Ran an Egg 2 on my BKO for years with good results. Old Spyders have some of the same issues, especially when using force-feed loaders, and are almost completely cured by using a "slower" loader.

A good newer option would be the Protoyz/PE Speedster loader. Basically a Revolution on steroids. It'll hit 10.5 ramp & isn't force-feed.

[Myrkul]

Yep, I tried a bunch of different hoppers on this, revys, halos, spires, ricochets, and probably a few more I'm forgetting about. It was still breaking paint like mad with every single one. My defiant had the same issue, as did my friends B2k4 and a random players B2k4 at the field. All of them were just handling the 0.682 field paint like shit. Not one of us has had a stack clip or barrel break since switching to the home brew cure bolts, and we are at least 2/3 cases in at this point.

[lhamilton1807]

Myrkul who did your bolt ramp mod? Vapor Bolts aren’t made anymore, but they look like they’re exactly the same thing as a stock bolt, but with o-ring grooves. I assume anyone who could machine that ramp could also machine grooves for o-rings (I assume 015) if I sent the bolt in.

I’m finally building mine up, and this guide will come in handy.

[Myrkul]

Myrkul who did your bolt ramp mod? Vapor Bolts aren’t made anymore, but they look like they’re exactly the same thing as a stock bolt, but with o-ring grooves. I assume anyone who could machine that ramp could also machine grooves for o-rings (I assume 015) if I sent the bolt in.

I’m finally building mine up, and this guide will come in handy.

KCCockerDoc did the original ramps on the vapor bolts for me. I believe he has done 7 vapor bolts total before they became impossible to find. The Vapor bolts are VERY different then the stock bolts. For starters, they weigh considerable less. 26 grams for the stock bolt, 18 grams for a vapor. They are also made out of Nylatron, not delrin. You can polish them out and get them so freaking smooth it's unreal. If you can find one, grab it. They last one I managed to find had the tail chopped down and was unfortunately too light, and I had to run my LPR higher to compensate. I eventually fixed it by using a beefier screw on the back to add weight, it weights 20 grams now, so a hair heavier then the original vapor bolts, but not much and it fixed the issue.

Unpolished vapor bolt with weight fix


Here it is all polished up and sexy


Unfortunately KCcocker doc does not have a good method for cutting the "o" rings in. I know back in the day someone was cutting "o" rings into the stock bolts using a drill press and a hack saw, but I've been unable to personally duplicate it.

Good news is, BMC Fabrication has zero issues adding both the ramps and the "o" rings to the stock bolts. He recently did these for me, and I just sent him another batch a few weeks ago.



They shoot absolutely freaking great. Both myself and OpusX have put a fair amount of paint through them and as long as you are feeding them right (Dye Rotor) there have been zero issues. BrickHaus has the blue one in his fishbone B2k2 LCD I rebuilt for him, not sure if he has tried to shoot it yet or not. It shot great for me...

https://youtube.com/shorts/buR3YeUpfSM?si=9IDFf1qHyyhts9Mf

The BMC modded stock bolts work better with #014 "o" rings, but you are correct that the vapor bolts use #015 "o" rings.

[Myrkul]

I would not chop the stock bolts down. If you go to light you'll need a detailed scale, a handful of screws, a Dremel, and several hours to try and get it back up to where it needs to be for the gun to shoot optimally. You'd be risking a ton of work for a largely unnoticeable gain. It's also worth noting that if you are using a factory board, their adjustment range for dwell is crazy small. The local proshop has also mentioned to me that back in they day when they were using B2ks competitively they would actively try to INCREASE the bolt weights to be heavier then stock so they could run their LPRs even lower (and be gentler on paint). 100% just send the stock bolt to BMC for "o" rings and a ramp, toss it in, and use it.

[lhamilton1807]

Ok, will do. Good perspective!
I’m ordering a vapor board & trigger. Will make a build thread when I have all my parts collected.

[Myrkul]

Hell ya! I love vapor boards. Be sure you have a 2k3/4 frame for the trigger, the vapor triggers don't work in the earlier frames.