pnuematic spear shaft compatibility and customization

[popolarbear]

say im currious if anyone has info on weather the pneumatic spear shafts are interchangeable between cressi and omer guns? i had a disscusion with one dive shop that claimed that almost all the pneumatics are manufactured by the same tooling shop and are nearly identical and interchangeble. my interest is that i love my omer but have been considering a backup cressi of the same size, and if they are compatible i can use my backup omer shafts on the cressi if need be.

final question is i have also read in a euro spero board about sanding down the loading end of the shaft to reduce the diameter slightly and thus increase the power of the gun by decressing the friction of the firing release. How dangerous a modification is this and has anyone tried this?? perhaps this end is only to hold the line clip and has no function in the triggar mechanism.

any suggestions very appreciated.

[Chapik]

I don't know if they intergangable, but I used in my Cressi SL70 shaft from Mares. I just change lower(bullet) type, the end which goes into the barel. It is skrew-on type.

[popolarbear]

yeh, thats what im looking at. is this lower bullet shape end at all critical to the functioning of the gun? ive never had one of these dissassembled to understand the mechanisms. also is it possible to load the pnuematic and leave it loaded and pull the spear out? if so then i would think the triggar locking mechanism is independent of the shaft, and at that point it probably would not matter what your shooting, it could be a smooth steel welding rod. (ha ha sorry for the crudeness in a finesse sport.).
questions is still up. i dont understand. could anyone shed light???

[cmburch]

Hey PoPolarBear,
The critical parts are
1.The shaft adapter end "butt" to fit securely in the barrel compression seat.
2.The correct diameter ID&OD ring to keep the shaft centered.
3.The correct diameter shaft.

The length can vary as long as it is about 2-4" outside the barrel when compressed.

If the "butt" adapter or the front ring gets loose and the shaft is out of alignment, it may permanently damage the gun when fired and may cause injury.

Pneumatics tend to have 7mm or 8mm diameter shafts with 6-7mm threading. I do not like purchasing metric because the threading is also metric and I have to re-thread to use our speartips. I do not like using mm-inch adapters. So I tend to use 9/32" or 5/16" diameter shafts.

I get shafts and parts from Ray Odor and also this shop in Florida.

http://www.spearfishing.cc/ (http://www.spearfishing.cc/)

http://www.scubasworld.com/products.php?cat=102 (http://www.scubasworld.com/products.php?cat=102)

If you want to stay with the standard metric INOX shafts, they are a lot cheaper from Europe.

There should be online manuals available for your guns.

Never leave a gun loaded. I can pull out the shaft, but I just unload. You can push speartip of the gun against a concrete corner or edge in the garage and put pressure against the gun to slowly release the spear.

Always store nose down to keep o-ring lubricated and can give it a drop of fork oil periodically.

The shaft has nothing to do with the trigger mechanism. So it does not make sense. The "butt" adapter just sits in a seat. Look in the barrel.

Maybe they mean it will release easier from the seat. It would not make any appreciable difference. A Mamba kit would, but they are too costly unless you are good at machining your own.

Post on deeperblue. There are pneumatic experts there. Ask that this thread be moved to a gun section.

From the SCUBAsWorld site, it looks like Cressi and Omer are different. Contact Ulises at SCUBAsWorld.

It looks like Omer and Cressi use an 8mm or 5/16" diameter shaft. Just need to check "butt" adapter and ring for fit.

[popolarbear]

thanks this is the info i needed. yes the omer has an 8mm which is almost identical to the us 5/16(i mic'd them last night). ive got some extra 5/16 stainless rods from some other project that if i could get them threaded id use them as backups. is that difficult to rethread stainless shafts??
also you mention
"If the "butt" adapter or the front ring gets loose and the shaft is out of alignment, it may permanently damage the gun when fired and may cause injury."
i am currious if this adapter can not be sanded down slightly in diameter, as when i load it and attempt to unload it is very snug and seems like a loss in firing momentum. this was as i understand one of the power modification i saw online, but the translation was bad so i dont realy understand what was the point.
also you mention the mamba kit. have you seen any good discussions on the fine points on machining one. i might be able to talk a machinist pal of mine into making one, if they arent too involved.

also thanks for the input.

[Ray Odor]

Hi, Popolarbear, thats a lot of good advice above. The only difference in most pneumatic shafts depends on the type gun you have. Most of them will take the 5/16" Spring Stainless Steel ones that we make with the exception of the Mares Cyrano, and it takes a 9/32". If your current gun uses a 5/16 D., don't try to use the 9/32. The O.D. of the 9/32 shaft adaptor is 5/16 and would go right through your slide. I mfg. all lengths of the 9/32 and 5/16" shafts in Spring S.S.
Need anything in shafts, call me.

Ray Odor Diving Service
2527 E.149th. Ave.,Lutz,FL33559
e- fishship@tampabay.rr.com
Ph.813-971-3368 Fax 813-364-6367
Web- www.spearfishing.cc