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Old January 31st, 2008, 21:02   #7
CDN_Stalker
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Next is chrony results from my MK23 springer, 10 shots of each BB weight tested. Quite interesting if you ask me! (I'll add that two nights ago I WASHED my 0.30g Bastards in dishsoap and warm water.......... including the bag. Why? Hop up puts a backspin on BBs by friction, and if each BB has a slight oily coating on it........all do, be it oil or graphite....... that reduces the amount of friction the hop up rubber can put on the BB, making you dial in more hop up to counter act it, putting a larger mass of obstruction into the BBs path down the barrel. This causes more inconsistancy and less accuracy. Mind you, I don't overly recommend this for AEG use, only bolt action will benefit from this, but I'd like to hear from AEG users that are willing to run dry BBs through their guns what they think. I've posted the BB washing thing on the Snipers Perch at www.airsoftretreat.com last year, and LOTS of bolt action users have found increased performance from washing their BBs. Nutshell, washed BBs allow you to run at lower hop up settings, reducing the 'blockage' of the BB's path, increasing everything including fps by a bit).

Ok, here's my results form tonight, chronying my TM MK23 springer with all the little Bastards.

0.20g

215.0
217.6
219.4
216.9
211.2
219.9
218.4
217.2
217.1
216.2

Mean: 216.9fps
Variance: 8.7fps

0.25g

198.3
199.1
198.8
201.1
199.1
199.5
201.0
197.6
201.0
201.0

Mean: 199.7fps
Variance: 3.5fps

0.28g

182.2
181.9
182.8
183.2
179.6
182.8
181.2
181.1
181.9
180.3

Mean: 181fps
Variance: 3.6fps

0.30g

183.0
178.7
180.3
181.7
180.9
181.4
179.3
181.0
181.7
181.7

Mean: 181.0
Variance: 3.7fps

Droppage, we have:

17.2fps decrease in velocity for a 0.05g increase in weight from 0.20g to 0.25g

18.0fps decrease in velocity for a 0.03g crease from 0.25g to 0.28g

and what confuses me, a 0.7fps decrease in velocity for a 0.02g increase from 0.28g to 0.30g, kinda shuts down (in this case) my rough rule of thumb:

"Estimate roughly a 10fps decrease in velocity for every 0.02g increase in BB weight." At least it works for AEGs, I assume because of the variable hop up unit. My springer has a fixed hop up unit that you can't set for BB weight changes.

As you can see, the consistancy between all the BBs fired through the most consistant gun I have is very tight, more so between the 0.25g and the 0.30g, less than 4fps difference which is extrememly damned good! Scarecrow has an extremely impressive product here!!! If he can get airsoft snipers across the continent (and beyond I'd like to see) 0.33g or 0.34g BBs as consistant as this, he will corner an almost non-existing market and will make tonnes of cash (I hope he shares ) In a lot of cases, 0.36g are only made by Straight, and really suck for size and consistancy between them, often varying by 0.1mm in some samples I've seen measured. And heavy BBs are crutial for long range shots with 'field limit' guns (between 450fps and 550fps with 0.20g BBs), and even more so if there is any wind at all.

Last edited by CDN_Stalker; January 31st, 2008 at 21:07..
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