hello here.. so, where can this tank block "industry brand" be acquired from?? really would like to have a bottle gun. by the way, nice project there. cheers
I found this video series earlier when i was looking up different info about this conversion. Starting at the 13:00 minute mark, is that the pressure testing jig you were talking about?
With the larger bottle, the tube won't have any problem supporting its weight in normal use. The potential problem arises that the bottle is sticking out further toward the muzzle. So if anything strikes it out there, it applies more leverage to the attachment points at the air tube. For example, if the gun gets dropped or knocked off a table, or if one were to slip and fall on the gun while trekking through the woods. That makes a stronger case for pinning the block. A couple more options for guarding against that type of damage is to fit a band around the bottle and barrel, or inlet the forestock to cradle the bottle (the stock need not go all the way out to the end of the bottle. Personally I would not want anything larger than a 17ci on a small bore rifle. I say that not so much because of a safety concern but simply from the standpoint of utility. A huge tank negatively affects weight and balance and I can't think of many circumstances where it is necessary to have so many shots on tap. I think a 13ci is a good sweet spot for .177 and .22 cal. Here are some examples of shot counts with a decent tune (1.2fpe/ci) or excellent tune (1.5fpe/ci). I somewhat arbitrarily picked energy levels for targets versus hunting but hopefully this will give an idea of what can be expected:
I've been asked a few times how I sealed the 2240 valve to the air tube using stacked O-rings.So while I was restoring a Crosman 150 this weekend, I used its valve to mock up the O-ring arrangement and took some pictures. So the pictures are not of a 2240 valve but it illustrates the concept.I will repeat, don't pressurize the tube until you've bolstered the valve retention.