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air rifle - attachment

Posted: Tue Jan 16, 2007 9:49 pm
by Pran
I have this attachment on my air rifle that I want to remove so I can measure the muzzle velocity.I'm not very sure how it is attached to the muzzle.The rifle is a 'Daws' make(anybody heard of it??).
Pran

Posted: Tue Jan 16, 2007 10:06 pm
by danish21
Pran

It is attached with ur air rifle's barrel and for better results u go to some good gun smith and he will cut this and then again he will do bluing of that portion of the barrel. By doing this your self there are chances of damaging ur guns barrel.

Danish

Posted: Tue Jan 16, 2007 10:34 pm
by Mack The Knife
Pran,

Muzzle velocity does not have to be measured at the very tip of the muzzle.

If you want I can measure the M.V. for you.

Mack The Knife

Re: air rifle - attachment

Posted: Tue Jan 16, 2007 11:01 pm
by Pran
Danish,
I'm unable to figure out how it's attached.The first sight was fixed and then this attachment.Doesn't look like it's screwed in either.Any ideas?

Mack The Knife,
Borrowed a velocity gauge from a friend(similar to the one in your pics).It's working fine on a 'national' rifle but shows 'BAD' when fixed on the attachment in mine.
Pran

Re: air rifle - attachment

Posted: Tue Jan 16, 2007 11:18 pm
by Mack The Knife
Borrowed a velocity gauge from a friend(similar to the one in your pics).It's working fine on a 'national' rifle but shows 'BAD' when fixed on the attachment in mine.
Probably not aligned correctly. The BAD reading can also be got if the rifle diesels badly or if the light conditions are poor. Read the owner's manual.

Mack The Knife

Re: air rifle - attachment

Posted: Tue Jan 16, 2007 11:25 pm
by Pran
Mack The Knife,
Was looking at your pics.This one is also combro and i don't have the owners manual.Tried realigning the gauge but then there's not much I can do when the muzzle is not seen.The OD of the gauge is same as that of the attachment which does not allow any realigning.
Pran

Re: air rifle - attachment

Posted: Tue Jan 16, 2007 11:31 pm
by Mack The Knife
Tried realigning the gauge but then there's not much I can do when the muzzle is not seen.
You have to realign the sensors with respect to the centre of bore. Makes no difference if you see the muzzle crown or not.
The OD of the gauge is same as that of the attachment which does not allow any realigning.
Loosen the knurled screw on the LCD panel side and slide the chrono up or down to align with the centre of the bore.

Mack The Knife

Posted: Tue Jan 16, 2007 11:35 pm
by Pran
[quote="Mack The Knife Bana";p="10361"]

Loosen the knurled screw on the LCD panel side and slide the chrono up or down to align with the centre of the bore.

[/quote]
That's what I've been doing.Will try a few more times tomorrow morning.
btw, what are the velocities you're getting on your rifles?
Pran

Posted: Tue Jan 16, 2007 11:40 pm
by Mack The Knife
Don't quite recall the last average taken but approximately, 810 fps in .22" and 940 fps in .177"

Mack The Knife

Re: air rifle - attachment

Posted: Tue Jan 16, 2007 11:41 pm
by Pran
WOW!

Posted: Tue Jan 16, 2007 11:44 pm
by Mack The Knife
How much did the National read on the chrono? Mention calibre and pellet used.

Mack The Knife

Re: air rifle - attachment

Posted: Wed Jan 17, 2007 12:17 am
by Pran
National .22 over 12 years old had velocities btw 475 and 510 fps
Pran

Re: air rifle - attachment

Posted: Sat Feb 03, 2007 12:04 pm
by Pran
After tinkering with the knurled screw managed to get readings on the velocity gauge and it was disappointing :( The National has a way better muzzle velocity than my rifle

Mack The Knife,
The reading's were taken 3" from the muzzle.Does that show a reading lesser than the actual muzzle velocity?

Pran

Re: air rifle - attachment

Posted: Sat Feb 03, 2007 5:02 pm
by Mack The Knife
Mack The Knife,
The reading's were taken 3" from the muzzle.Does that show a reading lesser than the actual muzzle velocity?
Only in theory and I doubt the chrono would have been able to tell the difference. In other words - NO!

Mack The Knife

P.S.: What are the respective calibres?

Re: air rifle - attachment

Posted: Sat Feb 03, 2007 6:20 pm
by Pran
Mack The Knife Bana";p="11453 wrote: In other words - NO!
That's depressing :(

Was in a mood to do some experimenting today.Dieseled the pump on my rifle and these are the 3 subsequent readings :

fps ftpds
458 6.98
398 5.27
396 5.22

Note that the first reading is close to twice that without dieselling!

Both rifles are .22 and I've used pointed pellets in both cases.Do wadcutters have a higher velocity?
Pran