SgNerf

Nice job T da B! Looks great!

Some interesting add-on info from my experience for those who are keen to also try this setup:

Note that the more air tubing in the setup, the more combined total internal air volume there is in the system, which is a factor in determining the PSI vs pumps... as T da B mentioned, 3 pumps from the Topeak Dual G pump in his system reaches 60+ PSI, which similar to my experience with the same setups using the same amount of additional air tubing and connections too.

For those who are planning a basic layout without the pressure gauge or safety valve (and without all the associated extra tubing and connectors), the total system air volume will also be naturally less in comparison, so you will notice a difference in PSI vs pumps.

I currently have modded AT3Ks which just connect the pump tubing straight through a quick-connect check valve and then into the air tank (so the overall amount of tubing used is much less), therefore this naturally results in higher pressure with the same number of pumps. In such basic setups, i've found that with 3 full pumps using the Topeak Dual G pump, the PSI can average around 70-75 PSI instead (which is the practical limit 'cos any higher and the trigger becomes too difficult to pull).

So far, i've not found much significant difference in actual ranges between both setups though... so i guess its just a minor balance/trade-off between slightly more internal air volume vs slightly higher pressure.

Just for general reference.

Yeah... at the last part of video when it was firing from 0:58 onwards, i also noticed the plunger rod isn't moving or releasing at all too.

Looks like either your blaster's catch plate spring popped out or somehow got stuck.

More Updates!

For Rampage users, the metal priming bar connecting the pump action grip and the bolt sled on some units may bend slightly due to heavier spring loads (ie. 8kg load springs or heavier), therefore this could cause the plunger not to catch by just 1-2mm

This is already a known issue when modding Raider units, and consequently it could also affect Rampage units too, as they both share similar priming systems. Experienced modders will already be familiar with it, but new modders should take note.

If this occurs, the solution is to either apply a layer of foam padding on the plunger head as a spacer or epoxy the priming bar to make it stiffer. Another alternative is to cut a ring of PVC pipe and epoxy it to the back of the bolt as a spacer too. These various methods will help to add abit more distance to the plunger rod moving backwards to enable it to catch properly.

Another Update!

I just bought a Buzz Bee Double Shot today to check out its springs (as i've been hearing that modders have been using them for their mods too). Took them out and compared them to my aftermarket ones.

Buzz Bee Double Shot Spring (left) vs. Aftermarket 8kg Load Spring (right).



They indeed have similar dimensions, though the double shot springs have abit more coils, they can still compress flat enough to fit within the space behind the Retaliator/Rampage catch area. I tested them and they work well in those blasters.

The double shot springs are noticeably lighter load though, they require around 30% less effort to compress... i compared them with another 5-6kg load spring which i custom made for my other modding projects and their loads felt similar. So i guess the double shot spring could be considered around 5-6kg load too.

They are stronger than the stock Retaliator/Rampage springs (which are estimated to be around 2.5-3kg), so they can be an alternative for those who prefer a lighter version of the 8kg load aftermarket springs that i use.

I did some ranges tests with the double shot springs and the shots averaged around just 10-15% less distance (compared to the 8kg load springs). Overall the range improvements are still quite decent, so they can be useful springs for those who have spare double shots to get them from.

Dimensions on the aftermarket spring you used?

The aftermarket springs i use are around 83mm in length, 17.2mm OD with a 1.4mm wire thickness.