The Diana 34 has been one of the most popular European spring-piston air rifles of the past 40 or 50 years. Itâ€™s often been touted as a sort of entry-level â€œmagnumâ€ gun, that is, one capable of generating over 12 foot-pounds of muzzle energy. Iâ€™ve owned around 30 or 40 quality airguns- that is, modern pellet firing guns with rifled steel barrels- but Iâ€™ve never owned a Diana Model 34, or any Diana spring-piston gun. That changed recently when I purchased a new Model 34 in .22 caliber.
There were three reasons for this purchase. First, I was looking for a lightweight break barrel gun for use afield. Something more powerful than my R7/HW30, and lighter and handier than my TX200 and ProSport. Second, I didnâ€™t own any airguns in .22, and last, I was curious about the performance of this very popular gun. Did its performance justify its popularity? It arrived today and I spent a few hours getting some initial impressions.
Itâ€™s not terribly different in appearance or construction from the typical German break barrel air rifles of the 1970s, when I first became interested in what were then called â€œAdult Air Rifles.â€ About the only concession to modern technology is the increased use of plastic parts, and the light-pipe open sights.
The sights are very visible, but the shape of the stock makes it impossible for me to get good sight alignment, and the front sight makes it impossible to grip the end of the barrel to get good cocking leverage. I removed the rear sight- Iâ€™ll put some short Allen screws in the screw holes to fill them- and removed the front sight blade and hood, leaving the plastic sleeve in place as a muzzle protector. (Iâ€™ll eventually replace that with a steel or aluminum â€œmuzzle brakeâ€ cocking handle to protect the muzzle and get a bit more cocking leverage. )
To replace the open sights I installed a 2.5×20 Barska scope I happened to have on hand. (It was previously used on a break-barrel .357 Magnum carbine I owned some years ago that I had built up as a woods gun.) The front lens element on this scope appears to be held between two threaded rings, so it should hold up well to spring piston gun recoil.
Cocking this gun generated a lot of noise from the spring, and the first few shots from this gun produced a significant amount of smoke and the smell of burning oil, something that put me in mind of the guns I bought back in the 70s and 80s. Newer and more modern guns, like my TX 200 and Pro Sport, and my Theoben, shot quietly and smoothly from the day they arrived. No smoke, either. Shooting the 34 is a trip back to the 70s or 80s, when it was assumed that the first thing you needed to do with any spring gun was to give it a proper tune-up. Strip it down, remove the excess lube, polish and de-burr the cylinder, etc.
After zeroing it in, in my basement 10m range, I shot a 5-shot test group:
As you can see from the vertical shot dispersion the gun was still dieseling. I suspect itâ€™ll settle down some as the excess oil burns off, but what it really needs is a better spring, a spring guide to quiet it and reduce internal friction and wear, and maybe an improved piston seal. Iâ€™ve often heard that the gun is over-sprung, and that going to a weaker spring can actually improve velocity as well as accuracy. Iâ€™ll probably rebuild it this winter, when Iâ€™m stuck indoors, using a Jim Maccari or Vortek kit. Iâ€™ve had good experience with both. My TX 200 was purchased direct from Maccari back when he was tuning rifles, and I installed a Vortek kit in my R7/HW 30 several years ago. Both are very smooth, quiet, and accurate shooters.
Other plans are to replace the plastic trigger guard with a metal one (I have what I believe is an HW or possibly FWB on hand that looks as if itâ€™ll fit) and if possible, find a better stock for it. Back in the 90s Maccari was making excellent unfinished custom stocks at very reasonable prices, and I purchased one for my HW77. Today all Iâ€™ve been able to find are complete custom stocks for over $1,000, which is overkill for a $300 rifle. It could also use a scope with higher magnification. 2.5x is fine for deer at 40 yards, but rodents are much tinier targets.
Iâ€™ve only put around three dozen pellets of various types through it, and while itâ€™s still noisy and rough shooting it has quieted down somewhat. I may try adding some heavy silicone grease to the spring and see if that quiets things a bit.