请教.177弹头直径上 .01mm 的差别

oldben

看到 2种 .177 弹弹：
Air Arms Diabolo Field .177 Cal, 4.51mm, 8.44 Grains, Domed, 500ct
http://www.pyramydair.com/s/p/Ai ... ins_Domed_500ct/715

Air Arms Falcon .177 Cal, 4.52mm, 7.33 Grains, Domed, 500ct
http://www.pyramydair.com/s/p/Ai ... ins_Domed_500ct/714

这个是3种，4.50mm, 4.51mm, 4.52mm
http://www.pyramydair.com/s/p/H_N_Field_Target_Sampler_Pack_177_Cal_Baracuda_Match_Field_Target_Trophy_Pellets_Domed_6_Head_Sizes_240ct/1101#
难道说.01mm 对射击会有明显的差别么？

或者是4.52mm的适合用在旧枪上？

happydad

百分之一毫米，这个应该是可以允许的公差吧？我猜啊！
毕竟气枪蛋主要是软铅，有一定变形空间的。
我用过大约20种不同厂牌的气枪蛋，有的明显上膛轻松，有的很紧要用力才压的进去。
我瞎琢磨是猜的啊，
还是请高人来回答吧。

happydad

还有一点，基本每个气枪蛋都有个屁眼，很明显是用来了更好的兜气的。我猜那个屁眼在兜气的同时被高压气体压迫很可能会小幅的变形，以使气枪蛋的外緣更好的跟随膛线旋转提高精度。不同的枪有的膛线深有的膛线浅，所以这个大一点小一点可能真的对精度影响很大。

pandamalone

google到了这个:

http://www.gatewaytoairguns.com/ ... p?topic=1629.0;wap2

Our research on pellet head sizes has proven to be somewhat entertaining.
What are you actually getting when you buy a tin of pellets claimed to be 4.51, 4.52 or so on.
We bought a tin of JSB Exact (4.53) and a tin of FX Premium (4.52)

Setting the micrometer to the claimed pellet diameter, we simply observed which pellets heads passed through the set gap. We didn’t use the micrometer’s ratchet for fear of deforming the pellet.

Here are the results of our measuring:

JSB Exact (4.53 mm) Sample of 10 pellets.

Set at 4.53 all 10 were smaller.
Set at 4.52;    9 were smaller.
Set at 4.51;   6 were smaller.
Set at 4.50;   3 were still smaller.

FX Premium (4.52 mm) Sample of 10 pellets.

Set at 4.52 all 10 were smaller.
Set at 4.51;   9 were smaller.
Set at 4.50;   3 were smaller.

也就是说虽然标称到4.52,但大多数还没有到标称直径

反过来还有人做过实验,测试不同直径对应的精度:

daved:
Hey, Johan,

Nice write up, and some nice research there.  So now that I've been nice, I'm gonna disagree with you :-).  Actually, the only thing I take exception to is your PS regarding chrony results.  Awhile back, I ordered a mixed sleeve of JSB Exacts, head diameters from 4.50 to 4.53.  With a freshly tuned Gamo CFX and a brand new Chrony Beta, I proceeded to test both velocity and accuracy.  The one thing I don't have is a scale, so I can't weigh my pellets.  But JSB's have a history for being very consistent in that regard.  So with the assumption that the weights were as advertised, I found significant differences in both velocity and accuracy, with that gun.  For whatever reason, the 4.52 was the best in all categories, accuracy, velocity, and deviation.  4.53 were slightly slower, the 4.50 and 4.51 were MUCH slower, and accuracy was, well, shotgun pattern rather than groups.  Don't have the data in front of me, but as I recall, the 4.52's averaged around 860 fps, with maybe a 5 fps extreme spread.  The 4.50's dropped over 100 fps, and like I already said, forget hitting what you were shooting at.

Interesting current note.  The gun used above has recently been converted to a gas ram.  And now it flings 4.52 Exacts all over the place.  The 4.50 JSB Match Diabolo S100 is my current control, on my 10 yard indoor range, that pellet will consistently group 5 shots inside a 1/4" bull.  The Exact 4.52 used to be almost as good, now it opens up to almost an inch at 10 yards!  The really weird thing is that the 4.51 and 4.53 now group slightly over 1/4".  Haven't tried the 4.50's yet.  Nor have I chronied any of them recently, but will be soon.  Just thought I pass along my experience.

Dave

似乎直径更大的初速更大,或许因为封闭更紧密?

pandamalone

http://www.vogelusa.com/pellettesting.htm

这个也可以参考下

lamborbikini

铅弹很软的，压进去时就和枪管吻合了。

精度还是要看枪本身的精度，还有铅弹的外形加工的精度

oldben

谢谢楼上几位的回复，那2篇文章读了很有帮助。

第2篇提到枪管加工的公差可以从4.48 mm 到 4.51 mm，这个是很正常的。就是用同样的钢料，在同一机床上用同一刀具，也极难加工出全部都是4.50 mm的枪管。

软软的铅弹能加工到 .01mm的精度，确实有水平。