Testing a Diana model 23 breakbarrel rifle: Part 2
by Tom Gaylord, a.k.a. B.B. Pelletier
Not as pretty as I would like. This Diana 23 has led a hard life.
Today, I’ll test the Diana model 23 for power. I don’t know what to expect from this airgun, other than not to expect too much. Certainly, the velocity will be low with a powerplant as small as this one.
I said last time that the 23 looks like a perfect 3/4 replica of a model 27. Well, that extends to the cocking effort, too. Believe it or not, this rifle cocks with just 10 lbs. of effort, making it the easiest-cocking breakbarrel air rifle I’ve ever tested. I don’t know if the mainspring is in good condition, nor do I know what the piston seal looks like; so, it may be premature to say this rifle is representative of all Diana 23s.
The trigger is a direct sear type, with no provisions for adjustment. That’s too bad, because even though it’s two stage and reasonably crisp, stage 2 breaks at 6 lbs., 14 oz. That’s a little high for the best work; and on a rifle this light, it’s very high. It will be hard to use the artillery hold as a result of this heavy trigger.
The first pellet I tried was the all-lead, 7-grain RWS Hobby. As light as it is, I’d hoped to see the best velocity figures with this one. Hobbys averaged 381 f.p.s. in this 23. The low was 371, and the high was 401 f.p.s. with a spread of 30 f.p.s. I would have thought they’d go about 50 f.p.s. faster, but I’m still getting used to this gun. At the average velocity, Hobbys produced 2.26 foot-pounds of energy at the muzzle. Talk about your pipsqueak air rifle!
Remember that I did oil the piston seal, which transferred oil to the breech seal, as well. This little rifle should be doing all that it can in its present state.
Crosman Premier lite
Next, I tried the 7.9-grain Crosman Premier pellet. I think this one is on the heavy side for such a small air rifle, but we’ll see. Premier lites left the muzzle at an average 376 f.p.s. Given what the Hobbys did, I thought that was pretty good. The low was 364 and the high was 389 f.p.s., for a spread of 25 f.p.s. At the average muzzle velocity, the energy was 2.48 foot-pounds.
JSB Exact RS
The last pellet I tried was the 7.3-grain JSB Exact RS dome. What a surprise they were! Looking at the velocity of the Premier lites and Hobbys, I guessed these pellets would be in the same neighborhood, but they weren’t. They seemed to fit the bore looser (not loose, but less tight than the other 2 pellets), and the average velocity was 452 f.p.s. That was what I expected from the Hobbys. So, how does a pellet that weighs even more than a Hobby go so much faster? I have to chalk it up to how well they fit the bore.
The low was 449 f.p.s., and the high was 454 f.p.s.; so, the spread was super tight, as well. At the average velocity, this pellet produced 3.31 foot-pounds of muzzle energy — which, while low, is still considerably higher than either of the other 2 pellets. I think this is one pellet I must test in the accuracy report that comes next.
As I mentioned, I’ve oiled the piston seal and breech seal and also rubbed down the entire rifle with Ballistol. I really don’t know the condition of the powerplant, but I suspect that it’s not as bad as the outside would make you believe. And the wood soaked up the Ballistol to shine almost like it did when the gun was new.
What I forgot to do
I’ve already tested this rifle for accuracy, and it turns out we’re going to be interested in the velocity of these pellets seated deep — instead of flush — into the breech. We’re also going to want to test this little rifle at 25 yards, so there’s still time for me to rerun the velocity test.
After the 25-yard test, I’m thinking of opening up this rifle and seeing the condition of the internal parts. I’m also thinking of stripping all the metal finish and rebluing the gun with Blue Wonder. I think this little rifle will be with us for some time to come.