Thought I should share my latest custom build I've done to a CR600w.

Picked this little beauty up recently and used it for my annual starling shoot around the house. somewhere the tally on starlings from this rifle is around 30 over the last month. 

This is really a brilliant rifle as is but decided to tinker. out of the box with Gun Cities .22 Javelin spear tip 15.74gr pellets I was getting an average of 508fps, I've drilled the internals out to 4.5mm and now achieving and average of 585fps. 

Next was a custom Carbon Fiber barrel shroud with an adapter to fit 1/2"x20 suppressors threads, I have fitted a Stealth .22 rimfire suppressor which does make it a little quieter than the factory one. 

Also I've made a bulk co2 adapter which has a quick release fitting for a 9oz paintball tank for more accurate shot strings. I do have a HPA tank to try through this running 1500psi at the regulator. 

See photos below. 

 cheers mike 

I know it has been a year since the last post on this thread but would love to knowthe results of your mods and if you made any further modifications? Seriously considering a CR600 but would like a bit more power than standard, to fit a bipod and perhaps a 24gram co2 bottle which can be filled and used in place of the 12g co2 canisters. Either that or a 2250b or 1322 to modify as I see you have also done.
Which is your preferred rifle, the CR600 or 2250?

Is drilling out to 4mm straightforward, or do I run a high risk of ruining a brand new rifle and voiding the warranty?  I don't personally have many tools but the people I'm stating with have an overflowing workshop. Trouble is it is litterally overflowing so finding a specific tool is a challenge.

Cheers

I think I will buy a cr600 tomorrow, so should have my own one to play with but I appreciate the offer.  Accuracy for pest control is probably the most important thing to me, I'm sure both will do a good job but I want a rifle I can shoot right away and that also pushes me towards the cr600.

Once I've had some use out of it and know it is working fine, I'll look into drilling out the internals to get a bit more performance.  I don't suppose you know what shot count you would get from a 12g co2 after the mods? As you have an external bottle I guess shot count isn't so much of an issue.

How have you fitted the bipod? From the pictures it looks like the bottle would be in the way for mounting one to the forearm.  I like the idea of a 24g aluminium bottle than can slide in where the two 12g co2 sapsules normally sit.

There is a dedicated air soft shop in Christchurch so I might well head in there and see what they have/could suggest for the cr600.

This idea from dvlnme/Mike sounds like the way I would want to go, or something very similar but without pictures and a limited knowledge of how these guns work I can't say I fully understand how this is put together.

 cheers mike"

I'll google 12g hpa cartridge now and see what comes up.

Someone in the comments claimed to get an additional 80fps from their CR600w by adding a slightly stronger hammer spring which would have the same effect as the spacer.

Any drawbacks I should consider? I read it might increase the weight of the trigger and add a little extra recoil. Of course the shot count will go down too.

Did you get a chance to take any photos.  I'd be interested to know how you are using 16grm capsules and also how your bipod is attached. Cheers

This seems to be after the pellet has been pushed from the magazine and once it is in the breech.  Does anyone else with a cr600w have something similar or does the bolt close smoothly all of the way.

My concern of course it that the pellet is catching and in pushing it forward the pellt may be damaged affecting accuracy.  I've yet to strip the rifle down but probably will do sooner rather than later.

The accuracy isn't too bad but there are certainly fliers. I attributed this to the pellets but it could be that they are getting damaged during loading.

A couple of years ago I bought 2 CR600W off Guncity on a $1 Res auction, as damaged. One had a scratched valve from factory swarf, so I polished that out, but the other had pellets stuck in the barrel from a rough loading breech. Easy fix.

They are easy guns to work on, so you could quite easily take the barrel out and smooth off the loading breech/port/leade thingy.

I only have the one type of pellet to try right now but will try some others soon.

That sounds like a good way to do it. I'm assuming a course to medium grid sandpaper would be ok?

It would be great to have a couple of ~36g bulk filled co2 containers that could be used without making any modifications to the rifle.  I think this is essentially what dvlnme said he has made in a different thread but I'm not exactly sure how he made his.

I'm assuming there is a reason why this isn't something everyone is doing, as on the surface it seems like a great solution.

One thing I'm unsure about is if you could simply drop one of the refillable capsules into the gun and have it work without making any changes to it?

I had seen that he hadn't been active on here for a few months and before I joined, so I didn't want to message him out of the blue about it.