S&T Tar 21 Professional

[BrightCandle]

Features

 

The S&T Tar 21 professional was released in 2014, its a electric blow back and in the USA its licensed by Elite Force, but here in Europe you'll find it under its manufacturers name of S&T. Be aware S&T has an earlier gun called the Sport and these gun don't share a lot internally, although the externals are quite similar. It has no lock back on empty magazine or any other fancy electronics. Its actually a reasonably heavy gun but the weight is all centred on the gearbox at the rear, making it feel light, especially on the left arm. Its got one small rail on the top and one on the right hand side, there is enough to fit a scope on the gun and for a flash light but not a lot else. I am told you can swap the charging handle and blow back to the other side if you want to but I haven't tried to. The battery goes in the front hand guard and it fits a 7.4V 2600mah vapex crane stock battery just about but it wont fit bigger.

 

Externals

 

The gun is all polymer on the outside, which considering the real one is like that as well is to be expected. The externals show some seams top and bottom. where the two moulds join and there are some blemishes around those edges as well which draw attention to the way its put together. The plastic of the main body of the gun is quite hardy, the plastic is certainly very strong and up to about 8mm thick in places. The main issue on the externals is probably the top sight mount rail, which is a little wobbly. The bolt looks reasonably good as it moves back and forth and its quite a loud clang especially next to the ear. Sometimes the bolt looks half way back and sometimes it doesn't, I am not entirely sure why it sometimes leaves the hop wheel showing a bit.

 

The trigger has a long pull before going off, partly because its a bullpup and partly because its just got a lot of tolerance. The trigger is pretty bad, its got no feel on break. The spring pushing the trigger overrides the feel of the gearbox switch so you wont ever get a nice bite point to pull to.

 

One of the oddest things about the Tar 21 is that it has no sling points.The stock has a hole that goes through and the Israeli's actually use a para-cord loop with a figure eight on the back to produce a hook point. This does give you a single point sling point but its quite far back and you would need a pretty high single point sling to have the gun sit high enough on you not to interfere with your legs. There is no front point on this gun either so out of the box you are not going to be using a two point sling (the ares has one with the front pin). I fitted a QD point in the upper receiver, the plastic is strong and a simple nut and bolt on a QD was all that was necessary to get a second sling point on the gun. Prior to making the second point however I used a paracord loop around the middle of the gun behind the hand guard and rear sight which gave me a more forward single point sling point.. It was a more balanced point to have the sling attached to the rifle but it wasn't ideal as the gun still tended to sit quite low.

 

In terms of magazines the MAG brand has worked well enough, feeding every time. They are a little loose and rattle about a little but they work just fine. PTS EPM mags also seem to fit and feed perfectly as do G&P mags, a lonex flash mag and some other random mags thrown to me in a skirmish as well. The magwell is standard M4 and it seems compatible with everything I have put in it.

 

Internals

 

Its got an OK enough gearbox shell. Its quite light and thin, its not ported, its not amazing or fantastic metal but its well machined. Its specific to the gun so its best not to break it. The gun came with a 400 fps spring and its about 25% shorter than most of the springs I have seen which is a little strange. The cylinder, piston head, piston, cylinder head and nozzle are all type 2 compatible (more or less) and the gears are all standard. The motor in the gearbox is a short type but its got a custom spring holding it in. I found the motor struggled a little pulling back the blow back, you could hear it struggling a little and getting warm. By default the motor seemed to produce about 12 rps. The gear has just bushings, no bearings that I remember seeing.

 

The gears are metal, they seem reasonably solid and I haven't so far had any issues with them. I needed to completely reshim them and it took a lot of shims to get them to stay still. The gearbox seems to be far too wide for these gears and they make a lot of noise initially. Even once shimmed they never really turn super smoothly but it can be improved.

 

I haven't really done much with the trigger switch I have left it completely alone. Its one of those components I fear will explode at any minute and its going to be hard to replace.

 

The piston head in mine had truly awful seal, it provided almost no resistance at all. The nozzle also has poor seal onto the cylinder head and there was not even an O ring in it. The cylinder head also didn't seal very well to the cylinder and was of the usual cheap plastic single seal type. So all in all you can expect the air seal to be below par in this gun.

 

The hop unit is plastic and it doesn't hold for more than a few hours before it needs resetting. Its also completely custom to the gun so you can't replace it. The original bucking half melted onto the inner barrel and really struggled to provide any useful hop effect and accuracy, I had to replace that immediately.

 

The inner barrel is brass and the inner finish was fairly rough. The barrel on the outside wasn't very flat , it rolls oddly but that doesn't say anything for the inner bore and its straightness.

 

The gun is held together with 3.5mm and 3mm hex screws and a few external pins. You are going to be using the hex screws alot if you take the gun apart an it takes a bit of time. To get the gearbox out you'll have to remove pretty much everything in the gun, including all the wiring (18 awg) and the trigger. There is no mosfet, no quick detach connectors and the wire is held in place with little plastic spacers, its never clipped down anywhere. The wires don't actually come loose but its not very secure and it certainly could come loose at some point, I have just had the gun open a lot.

 

The outer barrel is attached a little strangely. There is a plastic plate just in front of the gear box that it notches into and that is held down by 4 screws (that go into plastic). It holds the hop unit reasonably strongly against the gearbox and it also holds the barrel reasonably securely but I suspect given a bit of force on the barrel you could snap this mechanism of holding it down. I have actually gone face down off a tree with this gun and buried the barrel 6 inches in mud and dropped the gun on the flash hider indoors and it hasn't yet shown any sign of damage but its a concern as most guns have either no structure holding it specifically or a lot, this is all at the rear of the barrel and nothing holds the outer barrel to the front of the gun at all.

 

Customising the internals

 

Personally after a few games I felt the need to customise the following to improve the guns range and accuracy.

- Spring (used an SP120 and cut it down to size which dropped it right on 350 fps with 0.2s)

- Cylinder head (ASG dual o ring)

- Motor (ASG Ultimate torque)

- Piston head + piston (ASG, the louder large hole version)

- Nozzle (SHS metal red)

- Hop unit's arm (from a lonex M4 hop unit, hand to be sanded to clear the blow back)

- lapped the inner barrel (Hunterseeker 5 kit from air lab)

- R Hop (Z kit install, but actually it took a bit of dialling in to work well).

- The inner barrel required a little bit of shimming, just about half a millimetre front and rear.

 

I would basically recommend all of these to improve the gun. The air seal needs work and the basic bucking needs replacing.

 

Accuracy and range out of the box

 

Not all that great. The main issue is that about 1 in 4 shots was normal and went the sort of range you might expect from an AEG, 30m effective range. But 3 out of the 4 shots showed very little hop and would drop short. Thus the out of the box performance was inconsistent. This was actually easily fixed with a bucking change. The black bucking that came with the gun had gone off/was completely rubbish and a change to a G&G green helped immensely to make the gun more consistent. Then it reached out to the 30m range or so.

 

Upgraded accuracy

 

With the airseal fixed and the R hop in place and the barrel nice and shiny the range is quite good, around 60m effective doubling the base guns accuracy from its default configuration. Much of that came from the airseal improving the consistency of the gun enormously making 3-4 shots bursts at long range enough for a hit. The R hop further extended the range, its more than a person width however but certainly better than the gun initially. Now it only uses 0.28g BB's or above (R hops fault) and it seem to prefer 0.30g BBs for the best accuracy.

 

Problems

 

There are some problems with the blow back feature locking back on the charging handle. The lock point on the metal of the blow back is wearing out as time goes on and I anticipate at some point it wont lock back at all. Right now its unreliably locking back but I don't trust my fingers on it. This will deteriorate quite rapidly until it can't lock back at all.

 

The initial bucking as mentioned needed replacement.

 

The top rail wobbles.

 

Conclusion

 

My overall feeling is that if you are looking for a Tar 21 this is the most modern version out there. Its more upgradeable than the Ares and its a lot cheaper as well. But its certainly not the best build for a high quality and highly accurate airsoft gun and many other base guns around its price point are going to outperform it. The main limitation on upgrades is the hop unit, most of the other poor performance parts can be replaced but this part is custom to the gun and its going to be a problem. An R hop will reduce the dependency on the hop unit, but the hop unit can break and its going to be hard to get the gun up and running again. Replacing the initial hop rubber is likely going to be necessary for everyone as will a spring change for UK field limits unless yours was already downgraded. This I feel is a project gun that needs work to be competitive and not really skirmish-able out of the box, and it can be made so due to the M4 compatibility of most parts.

 

I love the ergonomics of the Tar 21, its remarkably well balanced and very pointable weapon due to its bullpup design and its weight distribution. I love the way you hold it and with the upgrades I am finding it to be a fantastic gun. However I can't say much good about the original internals they weren't great quality and the end result reflected that.

 

[BrightCandle]

I am starting to show a couple of wear items on hard to replace parts. The first is that the blow back metal is starting to loose its shape and its failing to catch on pulling the bolt back, so you need to hold the bolt back to adjust the hop. In addition the spring release is sometimes not working either and seems related to the failure for the bolt to catch.

 

The rail is attached to the top via hex screws into reinforced plastic and this is starting to loose rigidness. This is becoming an accuracy/optics issue with a heavier optic.

 

Neither of these is easy to get replacement parts for and I think that realises the issues with custom guns like this that don't have specific replacement parts on sale and aren't that well made to begin with.

 

Nothing too serious has gone wrong (that wasn't my fault) but since these parts started showing issues I thought I better mention it. No outright failure yet.