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SONYtec
14:48:25 Fri
May 14 2010

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Re: Barrel Measurements....

Thanks for posting that.

Prices look decent!



---
10/02/08 Black '05 Drozd STOCK.
3/13/08 YELLOW '03 DROZD, 9/17/08 full auto mod, 1, 3, Full. ROF mod soon.
07/07 Black '05 Drozd, 8/3/07 resistor mod, 9/20/07 full auto PCB. More to come! (Adjust pot. and solenoid)
Accessories: 8/24/07 PMI HPA tank, remote hose, 9/03/08 JimC barrels and QD adaptors, 10/01/08 JimC CAR stock adaptor. NEED HI-CAP MAGS!!!
 
 
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20perSecond
03:05:03 Fri
May 14 2010

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Re: Barrel Measurements....

http://www.iss-internationalshootersservice.com/

This guy is great. Sends you the stuff, THEN you pay.

Old school.

I hope everyone visiting his site can repect that.

  
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20perSecond
03:00:10 Fri
May 14 2010

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Re: Jamming....

If the barrel tolerances are "large" maybe the bore pressure leaks around the "lobed" bb, causing a jam. In a "tight toleranced" barrel the bore pressure gets trapped behind and forces the bb to move, thereby NOT causing a jam?

Just my two cents.
[1 edits; Last edit by 20perSecond at 03:00:59 Fri May 14 2010]

  
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SONYtec
01:13:11 Fri
May 14 2010

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Re: Barrel Measurements....

Can you post the link to where you purchased those copper coated lead bb's?

Thanks!



---
10/02/08 Black '05 Drozd STOCK.
3/13/08 YELLOW '03 DROZD, 9/17/08 full auto mod, 1, 3, Full. ROF mod soon.
07/07 Black '05 Drozd, 8/3/07 resistor mod, 9/20/07 full auto PCB. More to come! (Adjust pot. and solenoid)
Accessories: 8/24/07 PMI HPA tank, remote hose, 9/03/08 JimC barrels and QD adaptors, 10/01/08 JimC CAR stock adaptor. NEED HI-CAP MAGS!!!
 
 
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20perSecond
22:06:33 Thu
May 13 2010

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Re: Barrel Measurements.... (Update)

Haven't had any jams yet. I'll have to measure the new copper covered lead balls when I receive them. I ordered three sizes. 4.45mm, 4.50, and 4.52 to experiment with. We will see how it goes.

Interesting twist. (update)

Tried the copper coated precision lead balls. The 4.52's (.1779) don't work in anything. The exception being, picking through to find the ones that are "true" (if you have nothing better to do) will work in the original Baikal barrel ONLY.

The 4.5's (.1771) will work in the Baikal (2% jams) and the Jim C. 15" barrel (an important distinction) with about 10% jams. This is due to the Jim C. 15" barrel having a slightly smaller bore. To summarize....NOT the right size for either.

The 4.45 (.1751) will work in either barrel, ALTHOUGH, I am still getting an occasional jam in the Jim C. The velocities are higher in both.

The best for last (and most interesting). My new Jim C., 23" barrel (again, an important distinction) that I just received, seems to be the largest bore of the three (overall.. due to averaging measurements from both ends of ALL barrels). This one measured at .1764 at both ends! This barrel is perfectly straight and true. No jams EVER with 4.45mm. I am getting smoking velocities and accuracy. UNBELIEVABLE.

Note: The 23" barrel was excluded from the first two test as I hadn't received it yet. I would assume that it might accept the other sizes but haven't tried yet. These findings support my original measurements.

I hope this information is useful. Was a bit surprising to me.

:smile:
[5 edits; Last edit by 20perSecond at 15:11:02 Sun May 30 2010]

  
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SONYtec
18:39:32 Thu
May 13 2010

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Re: Barrel Measurements....

Have you tried measuring other daisy's? they shouldn't have a "lobe," nothings perfect.



---
10/02/08 Black '05 Drozd STOCK.
3/13/08 YELLOW '03 DROZD, 9/17/08 full auto mod, 1, 3, Full. ROF mod soon.
07/07 Black '05 Drozd, 8/3/07 resistor mod, 9/20/07 full auto PCB. More to come! (Adjust pot. and solenoid)
Accessories: 8/24/07 PMI HPA tank, remote hose, 9/03/08 JimC barrels and QD adaptors, 10/01/08 JimC CAR stock adaptor. NEED HI-CAP MAGS!!!
 
 
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drozdandconfused
15:01:16 Thu
May 13 2010

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Re: Barrel Measurements....

This is good info. What's funny is I had three barrel jams with my stock barrel. 2 using CO2, and 1 with HPA. I've had 0 with my JimC barrels. I only use Daisy zincs. I kept one of the bbs and measured it with a micrometer. It had a "lobe" on it, most likely from the zinc coating. You'd think with the larger bore on the stock barrel it would be less likely to jam. ?

  
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SONYtec
14:38:04 Wed
May 12 2010

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Re: Barrel Measurements....

Hi, and welcome.

Thats some great info, thanks for posting!!



---
10/02/08 Black '05 Drozd STOCK.
3/13/08 YELLOW '03 DROZD, 9/17/08 full auto mod, 1, 3, Full. ROF mod soon.
07/07 Black '05 Drozd, 8/3/07 resistor mod, 9/20/07 full auto PCB. More to come! (Adjust pot. and solenoid)
Accessories: 8/24/07 PMI HPA tank, remote hose, 9/03/08 JimC barrels and QD adaptors, 10/01/08 JimC CAR stock adaptor. NEED HI-CAP MAGS!!!
 
 
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20perSecond
05:52:53 Wed
May 12 2010

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Barrel Measurements.... (update)

Newbie, so go easy on me.

Just measured my Drozd barrel bore at .1776 thousandths of an inch. Baikal states 4.5mm (.1771) . I checked the Jim C. barrel and it came out to .174 thousandths @ 4.42mm.

Most of the zinc coated STEEL bb's are .173 and will roll out of either barrel. Maybe that's an additional reason Jim's are more accurate, in addition to their added length?

I found some Zimmerstutzen, copper coated, LEAD bb's at 4.52mm (.1779) that might only work in the Baikal barrel though. Also sold in 4.45mm (.1751) for the Jim C. Might be interesting to experiment with the slight differences.

Note: Measured barrel bores at each end with two different micrometers (for accuracy) to obtain the numbers stated above. This provides a general insight as to the size difference between the two manufacturing processes.
Jim C. says to get an accurate measurement, one should use "pin gages". He is correct.

Note: I am not claiming these measurements are exact, but rather, simply pointing out that the barrels are all slightly different in size. The RATIOS are consistently found between barrels irrespective of the actual size.

Has anyone else investigated this aspect?
[6 edits; Last edit by 20perSecond at 15:17:29 Sun May 30 2010]

  
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