Where is the power source?
The 12g is loaded in the grip frame by removing the left grip panel and inserting the 12g. What make these so special?
The history, the feel and the plan fun of the gun , the all most endless ways to customize. Are there different models/ styles?
There are a few different versions (letís call them that for ease) The first version can be identified by the lack of barrel sleeve , no ball stop in the top tube and sometimes threading on the rear of the feed tube. The second version can be identified by no barrel sleeve and a plastic ball stop on the feed tube. The third model has a removable barrel sleeve and a aluminum ball stop. The forth version started about late 1984 it has all the features of the third version plus a born on date under the right side grip panel. What parts can I get for it now?
If you are patient and search ebay you can find pumps, rear quick change valves and sometimes different internals. Phantom internals will almost be a drop in improvement with a small bit of work. To put them in you will need to switch the sears and remove the TPC set screw. (put some Teflon tape on the TPC to hold it set position) The next parts to improve the gun would be a Nelson spring kit (most local shops have these) To further improve the performance and better tune the gun a new power tube will be a necessary purchase. There are many choices old style Phantom power tubes, (available from CCI) Lapco power tubes (available from Lapco direct or Air Soldier) and Carter power tubes (available at Air Solider) While replacing the power tube it is a good idea to get a new cup seal there are two choices a Black Magic (available at Air Soldier & NW Supply) or a Phantom (available at CCI) If you do get a Black Magic be sure to get a 6-32 threaded cup seal as it will fit all the power tube listed. (so will the Phantom) Nelson still has a few parts in stock it would be best to call and ask what they have. I can give you a list of what they no longer have though ; body, valve, piercing pins, grip frame and OE grips. I bought a used one and the barrel and feed tube has rust what do I do?
First dissemble the gun second take a good assessment of the parts. If everything is salvageable get a shot gun cleaning kit or just a rod and a bronze/ brass brush in 12 & 10 gage also grab some fuzzy swabs too.. If you have a drill it will make things go faster. Attack the rust with the brush get is good as you can. If you have still a lot to go it may be time to think about having a airsmith flexhone the interior. If you have gotten the rust off pretty good it is now time to polish the barrel and breach I start with a copper cleaner called Twinky it get the surface to a nice level fast. Next I move on to a brass ,aluminum, or even a glass polish to get the barrel and breach to itís best. What can I do to the stock internals to make them better?
These are steel and have a textured surface most of the time you will need to take some of the material off to make it smooth. If you have a metal lathe this will be easy if not you can use a drill and a machine bolt. Find a machine bolt that fits snug through the 007 bolt you will also need a few nuts to hold it on. Chuck it up in the lathe or drill and get it spinning you can use tooling on the lathe but the drill you will need to use sand paper. I start with 360 wet or dry (I wet sand) to knock down the high spots next I move to 400 ,600.800. 1000,1500 then I hit it with crocus cloth and then a final buff on the buffing wheel. Remember do not remove too much material it will affect your efficiency greatly. Different Models
All of the Nel-Spots were made for Nelson by Daisy Air Guns under contract. The different versions can be broken down like this: First versions
; it may or may not have just Nel-Spot stamped on the top tube. It had a threaded back end of the feed tube for Aluminum paint tubes, it also has no ball stop to limit the paint to travel past the breach, the piercing pin will be straight and have no cup to help sealing, the grip frame adapter rail will have a straight rectangular slot. Some of these earliest versions will have a three tac welds holding the feed tube on, they will also not have a threaded feed port. This gun was made specifically for the forestry/ cattle industry. All Nel-Spot bodies were made of steel, the grip frames are made of pot metal Value on this one is tuff to pin down as very few survived and few have been seen. ( threaded feed ports) Second version
; quite similar to the above gun but will be stamped Nel-Spot 007, it will have no threading on the feed tube. This gun was made specifically for the forestry/ cattle industry. In good working condition with a good barrel and breach $60-80 Third version
; This gun will have a key holed shaped grip frame adapter plate for the piercing pin and cup to pass through, In later versions there will be a single screw for a ball stop just forward of the breach opening. This gun in latter stages was marketed for paintball, forestry and cattle. These guns are the more common ones found to be ex-rentals from fields. In good working order with no major corrosion issues $35-75 restored and excellent condition will be much higher. These guns are quite common on the market but demand is always high. Fourth version
: This is the final version with all the bells and whistles two piece ball stop, barrel sleeve that is removable so an extension can be put on to help with accuracy, (mostly hype) and the usual feature of the gun above. I lot of companies also mad upgrade parts for these from internals, long barrel bodies, triggers, and valves. These guns are not as common as the above gun though more were made but the bodies were more often replaced with ones from Line SI, Thunder Pig, TAG, J&J, AGS, etc. Price ranges are about the same as the above but finding one in NIB (new in bag) means you more then likely approach $200 for one. Spring and tube dimensions
Main spring is 2.0" long, about 0.48" od, 0.375" id
valve spring is 1.0" long, about 0.36" od, about 0.265" id Valve tube inside diameters
tube # inside dia. (tube brand measured)
-2 .112" (unknown)
-1 .114" (unknown)
0 .122" (unknown)
1 .134" (unknown)
2 .142" (unknown)
3 .152" (carter)
4 .172" (lapco)
5 .174" (unknown)
6 .189" (lapco)
tube # inside dia. (Line SI)
Line SI only made those 4 power tube sizes. Sear Info
not the store the very important piece of the puzzle in a Nelson valve gun.
Most manufacturers have over looked this piece and have made them so crudely.
I'll let the big secret out: they are all stamped out; only one company ever gave them the respect they deserve. ..... CCI. That's right Mike takes the time to actually have the sears finished after being stamped out. He also is the only one to do a major redesign to improve feel and release. The only other notable mentions are Air Power for using A2 tool steel in their Apex Elite and Lapco for a better shaped sear for the AT crowd. (marginal finish improvement too) Basic Nelson sears go like this
- original non AT (similar to a ranger sear) very rare to come across
- standard Nelson sear that is AT capable
- speed sear for faster AT ( Lapco and various after market companies)
The problem with the sears is they are punched out then heat treated. The ruff finish from the punch out and the heat treat make for smoothing the sear out a bit of a pain. Oil, water or diamond stones are what is needed to smooth out the sear. Smoothing out the sear improve the release, the take up, and latching. The smoother the gun operates the more efficient and predictable it will be. There is some caution to be warned of taking too much material off to make for a polishes surface can render a sear to the scrap yard. Tuning for Efficiency
Nelson style valve tuning for efficiency with 12 grams.
First off forget any notion of getting maximum efficiency from a vertical or bottom line layout. The key is to have the CO2 gas take the shortest path to the valve and remain in a compressed state. These techniques will also work on other set up but will not be as efficient as a direct and shot path to the valve. Things you may need to arrive at the most efficient set up.
Tools and such needed,
- Nelson Spring Kit
- Valve body back bottle, bobbed, or drop out any one of these will do.
- Power tubes of at least two different sizes these are not necessarily necessary but will make for an efficient set in the long run, I suggest a Lapco #4 & #6. (P is for Phantoms)
- A couple of valve seats with o-rings and a couple of cup seals put them together to have ready to go jet sets. These will make for easy tuning down the road but are not necessary.
- Nylon spacer 5/8Ē long x 1/2 ď OD x .375 ID can be found at your local mega home center in the hardware aisle. These usually come three to a bag we will make three different lengths.
- A light weight hammer Taso or Lapco will also be a nice addition but not necessary, both are out of production but with some hard work can be found on the internet.
- File, (small half round and one flat)
- hack saw (to cut the spacer down)
- Crocus cloth (rouge paper) for polishing the power tube
- some sort of drill to spin the power tube to ease polishing the power tube
- 12 grams plenty or a dummy set up for constant air
- chronograph and
- a note book
First thing clean every thing bolt & hammer, body of the gun, valve. Next polish the power tubes to make them smooth, donít go over board just want smooth and shiny.
Now assemble you jet sets if you have them (power tube, valve seat, o-ring, cup seal)
The next step is to cut down the nylon spacers the first I cut a 1/2Ē next at 3/8Ē and the last a 1/4". The first length may need a bit of trimming to allow the full travel of the power tube you will need to confirm this on the valve body. I cut the spacers down with a band saw but you may also use a hack saw. Try to keep the spacer as square and true as possible, use the files to clean up the ruff edges.
Next come the arduous part tuning, I start with the largest power tube, heaviest spring for the valve, and the lightest main spring with a light hammer. In general a heavy valve spring will be the most efficient one.
Put a drop of oil on the valve seat o-ring and the power tube where it intersects. Make sure to set the velocity adjuster to its midway position of adjustment, and the bolt & hammer have some lubricating oil on them.
Now starts the long process of tuning for efficiency, remember to let the 12 gram not chill to much take your time between shots donít rush. You may need to go through all the combinations of tubes, springs and valve spacers you made to get the best combinations for you set up. This is what the note book is for so you can know if you are making progress.
Remember to remove your gas source before opening up the valve to do adjustments. In my tuning I go for a velocity of about 265fps to 275 spikes will and can happen due to paint and ambient temperature.
Generally the largest spacer will give the most efficiency but rapid shots will suffer low velocity. There is always a bit of a balancing act that needs to be done to fit your style of shooting/ playing. The most efficient set up may not work for your style of play just make sure to have fun and continually adjust to the game.