Palmers Brass
Opsgear (any with matched paint)

Barrel Insert Kits:

Deadly Wind Carbon
Hammerhead

To answer your question:

It depends on what paint you were using and how old it is. You should be able to to a blow test: insert 10 balls, one at a time into your barrel. They should stick, but you should be able to gently blow them through the barrel.

Barrel kits with various sizes of inserts should correct this problem. Palmers brass barrels just work really well.

With this selection my teamates and I were within a 2-3 foot shot pattern minimum from 100 feet (we measured it as part of a shooting course). Most of the time our shots were within a 2 foot pattern.

The first two things that effect shot consistency are:

1. Using HPA instead of co2.
a. outside temperature will effect co2...you may need an expansion chamber
2. paint to barrel match.

There are a ton of threads on it- hit up the search feature for more info.

<edit>

Yes, for sure squeegee out the barrel, your paint may be oily. Even good paint gets oily at times, make sure you bring the squeegee out on the field with you.

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