Tell me about the Diana 20 T01

[HOSPassassin]

I inherited a Diana Model 20 T01 from my father several years ago and put it away, thinking it would duplicate my HW30s. I recently brought it back out and looked at it more closely. It is a very basic, no-frills youth rifle. The wood furniture appears well-finished in a dark stain. The metal bluing is ok... not as good as my Weihrauch but good enough to prevent rust over its estimated 25-30 year life.  It is even easier to cock than the HW30s and lighter to carry but it is somewhat more cheaply made. There is no butt pad, for example. I also noticed that the rear sight is very nice and click-adjustable but it is not solid metal like a Weihrauch rear sight. It is either hard plastic or some sort of cheap metal.

The trigger is a heavy single-stage that breaks fairly cleanly. I've experienced much worse. The recoil isn't much because of the low power level but the noise and vibration are prominent. I think it could use some Tune-in-a-Tube. It would also be a good idea to see if that trigger can be made lighter through lubrication or adjustment. It shoots at about 5-5.2 ft-lbs, depending on the pellet, and seems to be fairly accurate with light wadcutters. Most of the pellets I have tried in it shoot at just over 500 fps. So far H&N Excite Econ II, Daisy Wadcutters, and Daisy Pointed (surprise) shoot the best. I can get just over 1/2" CTC at 10 yards from a bench using the iron sights. I have not tried to mount a scope.

My impression is that it is an easy-to-cock, easy-to-shoot youth rifle that is better made than most chineseium or Turkish but not on par with higher-quality German or British rifles. I have some remaining questions:

1. Where was it made? I have read differing opinions about whether it comes from Germany or China.
2. How old is it? My father is departed and I never thought to ask him where it came from. I know he was shooting it at least in the early 2000's.
3. How do I make the trigger better? I have never felt the need to adjust a trigger before. This one is barely ok. I hope it can get better.
4. Will Tune-in-a-Tube or some other product smooth out the noise and vibration or does it need more in-depth work? Again, it works, but it's annoying.
5. Something inside it rattles when shaken. It does not seem to affect function. Should I go looking for it?
6. I can find no safety. Is there one somewhere?

[happymecanic]

I have one and I love it!

The Diana 20 is a better finished, re-branded Chinese B1, which is itself a copy of the venerable Diana 25. Expect about the same power as a D25, which was designed as a 7.5 joules airgun.

1- In China. Probably the first airgun Diana had made outside of Germany.
2- 25-35 years. IIRC, they were made from the early '90s up to the early 2000s.
3- Usual polishing job and a bit of moly or tungsten paste do wonders.
4- Polishing the spring ends and adding a steel washer on both ends should help a lot. Using a good tacky lube on those areas is the way to go.
5- That must be the cocking arm, mine does the same thing . Don't worry .
6- Nope, no safety. As you said yourself, it's a very basic, no-frills youth rifle. But very enjoyable for what it is.

Here's a thread I did on mine: https://www.gatewaytoairguns.org/GTA/index.php?topic=202939.0

[Toxylon]

Diana did drastic damage to their brand, a brand that was 60 years old when Weihrauch first turned to airguns, by adopting China guns on the side, as almost every discussion shows. "Bluing not as good as on a Weihrauch", when the bluing is Chinese!

Some time back Mike Driskill did an illustrating write up on how the kid-sized German Diana breakbarrels only seem of lower quality than the kid-sized Weihrauchs, because when those Dianas were being made, even the HW30 etc. were vastly more simple / barebones than today, where the kid-sized HW's are targeting 60 yo. men with disposable income.

[HectorMedina]

I inherited a Diana Model 20 T01 from my father several years ago and put it away, thinking it would duplicate my HW30s. I recently brought it back out and looked at it more closely. It is a very basic, no-frills youth rifle. The wood furniture appears well-finished in a dark stain. The metal bluing is ok... not as good as my Weihrauch but good enough to prevent rust over its estimated 25-30 year life.  It is even easier to cock than the HW30s and lighter to carry but it is somewhat more cheaply made. There is no butt pad, for example. I also noticed that the rear sight is very nice and click-adjustable but it is not solid metal like a Weihrauch rear sight. It is either hard plastic or some sort of cheap metal.

The trigger is a heavy single-stage that breaks fairly cleanly. I've experienced much worse. The recoil isn't much because of the low power level but the noise and vibration are prominent. I think it could use some Tune-in-a-Tube. It would also be a good idea to see if that trigger can be made lighter through lubrication or adjustment. It shoots at about 5-5.2 ft-lbs, depending on the pellet, and seems to be fairly accurate with light wadcutters. Most of the pellets I have tried in it shoot at just over 500 fps. So far H&N Excite Econ II, Daisy Wadcutters, and Daisy Pointed (surprise) shoot the best. I can get just over 1/2" CTC at 10 yards from a bench using the iron sights. I have not tried to mount a scope.

My impression is that it is an easy-to-cock, easy-to-shoot youth rifle that is better made than most chineseium or Turkish but not on par with higher-quality German or British rifles. I have some remaining questions:

1. Where was it made? I have read differing opinions about whether it comes from Germany or China.
2. How old is it? My father is departed and I never thought to ask him where it came from. I know he was shooting it at least in the early 2000's.
3. How do I make the trigger better? I have never felt the need to adjust a trigger before. This one is barely ok. I hope it can get better.
4. Will Tune-in-a-Tube or some other product smooth out the noise and vibration or does it need more in-depth work? Again, it works, but it's annoying.
5. Something inside it rattles when shaken. It does not seem to affect function. Should I go looking for it?
6. I can find no safety. Is there one somewhere?

If it is truly a T01, and 26-30 years old, that rifle was completely made in Germany. West Germany to be precise, at the Imperial City of Rastatt.
Chinese made airguns appeared in the DIANA "Action" line in 2018's catalogue, so anything before that, was German.
Your rifle should have 4 VERY SMALL numbers at the rear left side of the mechanisms tube, those are month/year of manufacture
If it  is in good condition, you have somewhat of a collector's item there, most of those "bottom of the line" models were treated as disposable goods, so not many survive in really good conditions. Think twice before barging in there with fossil fuel based lubes.
Good stoning of surfaces can improve a trigger MUCH more than lubrication, BUT you need to be careful to NOT CHANGE ANY ANGLE!
MOST surely what rattles is the cocking linkage between the breech block and the underbelly of the tube where it passes through to push the piston's skirt. Simple test:
Hold the gun across the "waist" of the forearm so that you are holding the cocking lever linkage and shake it. If it does not rattle, you have found the source of the rattle, if it still does, then it would be wise to learn why it is rattling.
No safety. Back then Humans were still trusted to think before acting.

HTH, keep well and shoot straight!





HM