Query on Air rifle caliber portability...

[rajeevdudi]

Dear Senior Members,
Greetings once again!

Today I am going to present a hypothetical query and seek wisdom from all experienced members in the forum. I am not sure about legality of this however I would like to know if there are any legal implication of doing this.

Suppose I have multiple ARs of .177 and .22 caliber I want to know whether it is possible to swap barrels between a .177 and .22 AR straight away without making any changes in the power plant per say or any other mechanical aspect related to parts. For instance say I have an old .22 AR with barrel quality intact and I wish to use it by replacing the barrel of a newer more powerful .177 AR( or vice versa) can I do it. (of course I am not overlooking the legal aspect of keeping the power under permissible limits as per law)

It may sound a stupid question to some of the more experienced seniors in the forum but I have been trying get it off my chest from by asking this.

Regards
Rajeev Dudi

[mundaire]

If you are talking about break barrel airguns, then you would need the following parts to be able to swap calibres:-
1. Barrel + barrel block (the metal block on which the barrel is fitted)
2. Barrel block detent assembly (usually a wedge or a ball, with a spring and a small screw to hold it all together)
3. Barrel breech seal (usually an O ring installed at the breech)
4. Cocking arm
5. Cocking arm screw/ bolt/ rivet (depending on the make model)

Some companies will sell you all of the above as a ready to fit set, others may sell some or each item separately. Depends entirely on the brand in question.

Now, about how the power plant will vary basis calibre. For springers, ceteris paribus, a smaller calibre (.177 in this case) will require a higher power spring to produce the same level of power as that of a larger calibre (.22 in this case).

Therefore, when you fit a .22 barrel on a .177 spring piston airgun, you will see an increase in power levels (if everything else remains the same). The reverse also holds true, i.e. when you fit a .177 barrel on a .22 spring piston airgun, you will see decrease in power levels.

Why is this? Simply put power (projectile energy) is a function of velocity and mass. For the smaller calibre, the mass of projectile is less, so to achieve the same power levels, it must be accelerated to a higher velocity, hence the need for using a higher power spring.

Cheers!
Abhijeet

[rajeevdudi]

Dear Abhijeet,

That is very informative piece for a novice like me, thanks a lot for explaining at such length.

Rgds
Rajeev

[Vishnu2017]

Good explanation, very informative,thanks abhijeet sir,

[Gunner_dh]

I had been thinking about the same, Swapping of barrels. I had seen an old .22 sidelever at great eastern however could not arrange for any gunsmith to do it. Nobody is willing to put that kind of labour for it.
It still shelfed at Great eastern

Regards
dh