Accuracy testing

Accuracy testing

Postby Paulmurd » Thu Oct 05, 2017 3:46 pm

Has anybody tried an accuracy test without using a silencer or stripper on their 400?

Thanks
Paulmurd
 
Posts: 156
Joined: Tue May 03, 2016 6:37 am

Re: Accuracy testing

Postby Archer50 » Thu Oct 05, 2017 5:02 pm

Paulmurd wrote:Has anybody tried an accuracy test without using a silencer or stripper on their 400?

Thanks


Yes. On my .177 Classic I found no difference in group size at 50 yards between the solid (ie no holes) standard muzzle weight, an air brake and a Weihrauch moderator. The groups were slightly but definitely bigger with a bare barrel (sorry, lost the spreadsheet so I can't quote numbers). The difference with the bare barrel might be because I find that the gun needs some additional weight up front to steady my aim. In each case the POI was different. For instance it was about an inch low and left with the mod, compared to the air brake. I assume this is down to barrel harmonics.

The air stripper (Rowan) was different. I found that at best, it did nothing compared to an air brake/muzzle weight, but if not very carefully adjusted, it made things a lot worse - I understand the theory and I know some people get good results with them, but personally I never use any sort of stripper.

Alan
Archer50
 
Posts: 106
Joined: Mon Jun 20, 2016 5:06 pm
Location: Perth

Re: Accuracy testing

Postby Paulmurd » Thu Oct 05, 2017 5:19 pm

Many thanks for your input mate, much appreciated.

Paul
Paulmurd
 
Posts: 156
Joined: Tue May 03, 2016 6:37 am

Re: Accuracy testing

Postby TenMetrePeter » Thu Oct 05, 2017 6:02 pm

Archer50 wrote:
... For instance it was about an inch low and left with the mod, compared to the air brake. I assume this is down to barrel harmonics.

Alan


More likely venturi/pitot effect. The pellet cannot be exactly concentric with the moderator exit hole. The part of the hole nearest the pellet will have higher velocity air flow. The resultant lower pressure will pull the pellet even nearer. It should however be a relatively constant effect so POI will be affected but not group size. Using a .22 mod on a .177 barrel is a good compromise.
S400 MPR Precision 10m.
Green Belt in Ludo
My Youtube
User avatar
TenMetrePeter
 
Posts: 585
Joined: Wed Jun 29, 2016 5:40 pm
Location: Luton England NOT EU

Re: Accuracy testing

Postby Raj » Thu Oct 05, 2017 8:10 pm

I am itching to explain the difference between 'accuracy' and 'precision' but I wont. Anyone can google it ...... 'accuracy' vs 'precision' :) https://celebrating200years.noaa.gov/ma ... side1.html


And yes ... I have tried the same regulated rifle with all 3 scenarios ... 1. Bare barrel, 2. Silencer and 3. Stripper.
The group size was progressively better (smaller) in the order I have listed above.
“It's the Indian, not the arrow"
User avatar
Raj
Moderator
 
Posts: 1896
Joined: Sun Feb 15, 2015 9:36 pm
Location: Rugby

Re: Accuracy testing

Postby gdavison » Thu Oct 05, 2017 8:15 pm

Raj wrote:I am itching to explain the difference between 'accuracy' and 'precision' but I wont. Anyone can google it ...... 'accuracy' vs 'precision' :) https://celebrating200years.noaa.gov/ma ... side1.html


And yes ... I have tried the same regulated rifle with all 3 scenarios ... 1. Bare barrel, 2. Silencer and 3. Stripper.
The group size was progressively better (smaller) in the order I have listed above.


it has cats in it :)

https://www.youtube.com/watch?v=_LL0uiOgh1E
AA FTP900 - Falcon T50 10-50 * 60
AA S510 Ultimate Sporter RatWorks Tuned - Hawke SW 4-16*50
AA S510 RatWorks Tuned - Hawke SW 10*42 1/2 MilDot  - ACZ Stock
AA S510 30 Year Anniversary .22 - Hawke Panoramic 4-12*40
gdavison
 
Posts: 308
Joined: Tue Feb 17, 2015 6:43 am
Location: Baughurst

Re: Accuracy testing

Postby Raj » Fri Oct 06, 2017 2:51 pm

Love it !!! The number of folks in the gun world who go on about 'accurate guns' is quite funny.
To keep it simple, Guns can only be 'precise' or 'not precise'.
The accuracy comes from the nut behind the butt.
“It's the Indian, not the arrow"
User avatar
Raj
Moderator
 
Posts: 1896
Joined: Sun Feb 15, 2015 9:36 pm
Location: Rugby

Re: Accuracy testing

Postby Axelrod » Fri Oct 06, 2017 4:12 pm

Coupled with inaccurately made guns. :lol: dave
Axelrod
 
Posts: 106
Joined: Sun Feb 15, 2015 3:44 pm
Location: Almeria Spain.

Re: Accuracy testing

Postby Archer50 » Fri Oct 06, 2017 5:56 pm

Raj wrote:I am itching to explain the difference between 'accuracy' and 'precision' but I wont.


But we all know what the OP meant and that's why I carefully talked about 'group size' and 'POI' :D

Alan
Archer50
 
Posts: 106
Joined: Mon Jun 20, 2016 5:06 pm
Location: Perth

Re: Accuracy testing

Postby cyclopse » Fri Oct 06, 2017 5:59 pm

And yes ... I have tried the same regulated rifle with all 3 scenarios ... 1. Bare barrel, 2. Silencer and 3. Stripper.
The group size was progressively better (smaller) in the order I have listed above.

Same as Raj.
I had a s400 .22 tench reg for 10 years I have shot it with nothing on the end, had an AA silencer that I used for a long while and then an Air stripper, properly adjusted when I was doing HFT with that gun for a couple of years including 3 AAOC annual bashes. I'm afraid I was never a pellet on pellet man, too many twitches but the stripper was definitely best.
John
AA S400 .22 Carbine
AA T200 Mk2 .177
BSA Goldstar SE .177
HW99 .177
User avatar
cyclopse
 
Posts: 29
Joined: Sun Apr 05, 2015 3:57 pm
Location: Lancashire


Return to General airgun chat

Who is online

Users browsing this forum: No registered users and 4 guests