Homebuilt 9mm Handgun Suppressor

[Jughead]

What is the purpose of the notches and pin on the center barrel? Obviously they prevent free rotation except during a firing event, but why is that necessary?

Neil

@sossol , I did mention it in the original post, but maybe not clearly.

When any additional weight is added to the front of a firearm barrel, the point of impact changes. This is due to a number of factors that take place within a micro second while the round is travelling down between the baffles. Slight inconsistencies between the baffles, slight microscopic deviations in the movement of the barrel/suppressor or slight play in the mechanism that is needed for free movement will cause a round to wander off course. Normally these inconsistencies are consistent, and the round will consistently wander off course in the same direction.

Firing 5 rounds, I can consistently hit a 50mm (2 inch) circle at 15 meters without the suppressor. As soon as the suppressor is fitted however, the point of impact moves by about 3 inches to the 4 o'clock position. That is where the inconsistencies within the suppressor/barrel setup will lead the round. What I have built into the Nielsen device though, is the ability to change the inconsistencies by rotating the suppressor. Rotating it by one notch in relation to the barrel now moves the point of impact by 2.5 inches to the 6 o'clock position. One more notch of rotation will move it again by maybe 1.5 inches to the 9 o'clock position. I can continue to do this until the barrel/suppressor relationship is such that I am back to firing within my 2 inch circle at 15 meters.

Hope this makes sense.

[alainbiggun]

c'est un phénomène très connu,et là,bien maitrisé ! bravo pour l'idée