.177 bore Diana?

.177 bore Diana?

Joined: February 6th, 2013, 10:29 am

December 5th, 2016, 7:39 am #1

Been trying to get an answer for years but no one seems to know...
I have been told.Chinese .22 bores are large, mimicking early British bores but is this also tru of the .177s?
I have shot.452 primarally thru my pet sidelever old 1970s Snowpeak which has a really fine barel and despite country of manufacture is a great rifle!
H&N FT.452 seem to shoot best but so do cheap Crosman points!
I'm guessing the head riding on th rifling causes this?soft vskirted JSBs also shoot ell head again is.452.
Any thoughts on this?
Dave
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Joined: June 4th, 2013, 4:42 am

December 5th, 2016, 6:32 pm #2

Who makes the claim? Surely such a claim is qualified by a certain brand and/or vintage. For example, there was a trend in the .22 Crosman barrels having oversized bores a few years ago.

All I can say is out of 50+ Chinese air rifles that have been through my hands in the last 5 years, I have seen no evidence that they have oversized bores. It has been a pretty even mix of mostly .177 and .22 and I have slugged a good many of them to look at how pellets engage the rifling. On the whole, large pellets show deep engagement and small pellets show shallow engagement.

In fact, I've noticed Lothar Walther barrels to have a comparatively looser fit until reaching the choke.

Conventional wisdom is that you need distinct engraving of the head to get good results but that is not what my testing showed. I've certainly had barrel/pellet combos that engrave deeply and shoot great but some of my best results have been with JSB pellets that barely show burnishing of the rifling around the head. As long as the pellet head is not so small as to permit it to tip in the bore, it has just as good a chance of shooting well as one that gets engraved.

Harry has written of similar observations in these posts:
http://www.network54.com/Forum/79537/me ... +long+time+.
http://www.network54.com/Forum/79537/thread/1442458875
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Joined: March 28th, 2002, 6:54 pm

December 6th, 2016, 1:13 am #3

Been trying to get an answer for years but no one seems to know...
I have been told.Chinese .22 bores are large, mimicking early British bores but is this also tru of the .177s?
I have shot.452 primarally thru my pet sidelever old 1970s Snowpeak which has a really fine barel and despite country of manufacture is a great rifle!
H&N FT.452 seem to shoot best but so do cheap Crosman points!
I'm guessing the head riding on th rifling causes this?soft vskirted JSBs also shoot ell head again is.452.
Any thoughts on this?
Dave
at least nothing like the "wont shoot anything accurately" oversize bores in many Benjie 392's of recent vintage.

The old snowpeaks and fast deers had remarkably nice bores(in .177) especially considering the price, and didn't seem pellet fussy or oversize, but I don't have any old Chinese .22's other than a couple project QB 78's of unknown vintage, and they seem way less pellet fussy, and more generally accurate, than the aforementioned 392's.

A lightly massaged QB barrel in.177 is as accurate as anything I own at 10-30 yards, with a variety of pellets, a somewhat more pampered .22 QB barrel will shoot groups as nice as the LW barrel that's on the same gun now...I honestly don't know how the Chinese barrels often outshoot crosman barrels,in spite of wandering bores (cut any of them and the hole will be off center)

Turkish(hatsan) bores in the low cost guns at least, are horrid in comparison, but occasionally I'll find a cheap Chinese made break barrel of recent manufacture with real bore problems.
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