Seal Sizing

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Seal Sizing

This seal is made from a tough new material  that lets it be sized by even a novice and will handle even hotter springs than the factory. If you’re a pro at resizing seals then you do just as you normally would. This seal is ideal for varied tolerances runs of guns. Or suitable for the Pro FT guy that wants a perfection fit and also to  adjust velocity to his preferred level through sizing. On non AA guns this fits all the guns the Apex small seal does without modification. 
                              
Always install seal before sizing- unless it’s impossible without damage.

 If not follow these basic instructions. (These can be adapted to your personal experience and tools you have available)

First take the new seal unmodified with some moly paste or Webley seal oil and put the new seal in the gun. (I do not even put the action back in the stock, saves time and if you’re careful it's not a problem. However I have been doing this for 25 years-so do what you’re comfortable with.)

Fire 5 shots to set the seal. Chrony it and see where its at. If it's where it should be, leave it alone. If not remove it from the gun and it will show you a dark line just at the front edge or just behind it. Use the abrasive cloth supplied to make this mark disappear. ( test it in the compression tube a few times to see how it feels)
 When its snug and not loose or too tight then put it back in the gun and fire a few shots to settle it in. If its close to where it should be, leave it alone as it will pick up in power down the road.

The seal can be sized on a lathe or in a electric hand drill or using a Dremel tool if super careful. (Or just by rotating it in your hand against the abrasive-best if fitted to the piston.  Keep the natural seal contours as they are) You should get a semi gloss edge on your newly sized seal. This material sizes super well and very little effort is required. The picture shows a rare condition where the last two inches of compression tube towards the port had a bulge in it that made seal fitting a no win proposition. So I had to remove the bulge and resize the Tesla seal to fit. A gain of 65 fps took place in a 22 HC.