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flightsimmer · Member

Hi guys and girls;

Being an old retired fart I have the time and interest in checking BB gun and BB accuracy.
I bought a new Daisy #25 pump cocking BB gun this spring because when I was a kid I always wanted one but could not afford one back then so I had to use an old beat-up Red Rider that someone must have given me.
Anyway, this new model #25 was great but it didn't shoot very good and the target looked like I was using a shotgun, groups were sometimes in the 9"to 11" range at five meters (16.4ft.).
So I set out to find out why because I remembered that when I was a kid a friend of mine who had a model #25 and let me shoot it once in a while could hit anything, it was very accurate.
I started out by checking out the barrel and found it to be .178" and it seemed to be fairly uniform through out the length and it looked straight by using the light reflection method inside the tube like barrel straighteners used to do (and may still).
Then I checked out the barrel crown, it makes a big difference in powder burners (firearms) and that's when I noticed that the crown was very lopsided, that's bad.
The barrel on the #25 is a tube, like a soda straw and it fits snugly inside the loading fixture that holds the BB's, so I pulled it out with needle nosed pliars and looked at the crown on the other (reciever) end and found it to be very even so I just flipped it end for end and put it back together and shot it.
Now it was shooting much better, roughly 1-1/2" groups at 5 meters with Crossman "CopperHeads" and about the same with Daisy "Precision" tin plated BB's, but I remembered better accuracy than that when I was a kid.
So I searched the internet for post like this one to learn all I could and then I emailed Daisy. They were very, very helpful and sent me altogether 3 tested barrels sized .177" to try out plus a supply of their "Avanti" match BB's which I couldn't find anywhere locally and shipping is more than the BB's themselves.
I found two of the barrels were excellent and measured .177" at the muzzle and shot roughly 1/2" to 3/4", 5 shot groups at 5 meters but they shot to two different points of aim, one was dead-on so I used it to do the BB testing.
To start the testing I cleaned the barrel bore throughly with Hoppe's and Q-Tips and left it dry so that oil residue would not effect the results.
Then I spent more that an hour sorting BB's by size and found all of them that I checked to be .171 to .173 with most being .1725 and I only used uniform sized BB's for the test unless otherwise noted.
Then I selected 20 of each batch to shoot.
I shot off of a rest at 5 meters and when I finished I showed the results to my wife and she said "I can't see any difference, they all look the same" and she was right, they were all roughly 1" to 1-1/4" groups. So much for that! I did however have many, many 5 shot groups that could be covered by a dime but 20 shots always opened them up.
So then I took 20 of the reject BB's and shot them, same results, maybe a tad bit better.
So then I found one of the smallest CopperHead BB's at .171" and shot it 20 times with much the same results except I noticed there was less verticle stringing of the group compared to the .173" Avanti BB's which makes me suspect that maybe veloscity was more uniform with the .171" BB. I examined the BB that I shot 20 times with a magnifier and could not tell it had ever been shot. I had a carpet backstop.
I wish that I had had a chronograph but I don't, yet, maybe this summer. I did get a chronograph tape from Pyramyd Air when I bought it that said the average fps was 305 -315.
So all in all I don't think I proved anything except that the BB's didn't seem to makes much difference in my testing but I am satisfied with the results and I'm tired so I'm gonna go take a nap, you can do that when your retired you know. Bye.

10mm, when you care enough to send the very best.

under500fps · Veteran Member

From one retired old fart to another retired old fart,
my Crosman 781 shoots Copperhead BBs at 390 fps according to my Chrony F1
and it has an accuracy of about 2 inches from 25 feet .