Posts Tagged ‘air rifle’
by Tom Gaylord, a.k.a. B.B. Pelletier
Benjamin Titan with Nitro Piston has people talking.
Lots of interest in this air rifle — even from those who normally wouldn’t look twice at a gun of this kind. I guess it’s the low price that has folks talking.
Today is velocity day and a chance to become better acquainted with the test rifle. If you just found this blog, read Part 1 linked above. A short introduction is that Nitro Piston is the Crosman-trademarked name for a gas spring. Performance of a gas spring is a bit different than for a conventional coiled steel mainspring, though in the end both are spring-piston airguns. A gas spring uses compressed gas instead of a coiled steel spring to push the piston that compresses the air for each shot. Gas doesn’t suffer from being compressed for long periods, so you can leave a gun like this cocked for months and the power should not be affected. That isn’t recommended for reasons of safety, but it does allow hunters to carry their rifle cocked and loaded all day. Gas is also less sensitive to temperature changes, so gas springs retain their power better in extreme cold, where the lubricants in steel spring guns thicken and slow down the piston.
This particular rifle has lower power than most gas spring guns, and as a result, is easier to cock. The test rifle requires 33 lbs. of force to cock, where a conventional gas spring gun is often closer to 50 lbs. Still, 33 lbs. is not light. It takes an adult hand to cock this rifle.
Crosman built this rifle for the Illinois airgun market that used to mandate a muzzle velocity of less than 700 f.p.s. That law was changed, so the guns that remain are being sold directly by Crosman. I bought one because I’m a fan of lower-powered gas spring airguns.
The first pellet tested was the one that was included in the package with the rifle — a 250-count tin of Crosman Destroyers. The Destroyer is a hollowpoint pellet with a pointed tip inserted in the center of the hollow point. They’re made of hardened lead and weigh 7.9 grains, nominally. This is a pellet I don’t believe I’ve ever tested, so I’ll be doing so within this test. I see the customer reviews of the pellet are all over the place, so they aren’t that helpful. I’ll test them for accuracy in this rifle; and if the accuracy seems to warrant it, perhaps also test it in my R8, which we all know to be a very accurate breakbarrel.
Destroyers averaged 699 f.p.s. in the test rifle. They ranged from a low of 672 to a high of 722 f.p.s., so the spread was 50 f.p.s. That’s too high, but I think the rifle may need to break in a little to get rid of some excess oil in the compression chamber. Once it’s broken in, I think the average will be down around 685 because that was the direction the pellet seemed to be heading as I shot it. At the average velocity, this pellet produced 8.57 foot-pounds of muzzle energy.
This pellet loaded tight in the breech. I’ll have more to say about that in a bit.
The RWS Hobby pellet is one of the lightest pure-lead pellets on the market. It’s always the one I use to test the top velocity of an airgun because it’s often very accurate as well as fast. That makes it a real-world pellet and not just a bragging-rights trick pellet that will only be used for velocity numbers. The Hobby is a wadcutter, so it’s also good for pest elimination at ranges below 25 yards.
Hobbys averaged 708 f.p.s. in this rifle. The range went from 696 to 722 f.p.s., so a spread of 26 f.p.s. With the Hobby, there was no trend toward lower velocities in the string of 10 shots, so I think the average is representative of what this gun will always do. At the average velocity, Hobbys produced 7.79 foot-pounds of energy at the muzzle.
Hobbys loaded even tighter than Destroyers. The back of the skirt stuck out no matter how hard I pushed it into the breech. However, closing the barrel did push the pellets flush without damaging the skirt.
The 7.9-grain Crosman Premier averaged 665 f.p.s in the test rifle. The range went from 655 to 680 f.p.s., so a 25-foot-per-second spread. These pellets fit the breech very well and seated flush with the end of the barrel using finger pressure alone. At the average velocity, Premier lites produced 7.76 foot-pounds of muzzle energy.
A pellet-seating experiment
I’ve mentioned that two of the three pellets tried were hard to seat because they were tight in the breech. I thought it would be instructive, therefore, to conduct a little experiment to see how deep-seating them affected things. I guessed it would lower the average velocity, but it might also make the velocity spread a little tighter.
I chose RWS Hobby pellets for this test because they were the tightest in the breech. Using the adjustable pellet seating tool that comes with the Pellet Pen and PellSet, I seated each Hobby pellet about 1/16 inch into the breech. The average when seated this way was 686 f.p.s., compared to the 708 f.p.s. when seated by finger pressure alone. The range went from 678 to 691 f.p.s. — a spread of 13 f.p.s., compared to the 26 f.p.s. spread for the finger-seated pellets. I think this result is interesting enough to warrant a special test during the big accuracy test that comes next.
Although the trigger still has a long pull and buckets of creep, it releases at a pretty nice 4 lbs. on the money. If I can shoot with discipline, it may not influence the accuracy as much as I originally feared.
Observations thus far
Well, the rifle is harder to cock than I originally thought. I thought it was just me getting weaker, but apparently I’m still able to cock a springer — this one just takes more than I think it should for the power it delivers. Ed Schultz of Crosman told me when I tested the Benjamin Legacy with Nitro Piston in .22 caliber that they were never able to get a .177 to shoot and behave as well as the .22. That must have something to do with the smaller bore diameter, but what it might be I have no idea. If true, it suggests that a .25-caliber low-velocity breakbarrel with Nitro Piston might be the nicest airgun of all, though I doubt we’ll ever see one.
The firing behavior of this rifle is very nice. It fires with just a small forward jolt and no vibration to speak of, though I did need to tighten all the stock screws once during the test.
The velocity is bang-on the advertised speed. It didn’t take any trick pellets to achieve it, either. The velocity is in a very nice place for accuracy, and the smooth behavior of the rifle can’t do anything but help it achieve its absolute best. So, I’m expecting good things on accuracy day.
by Tom Gaylord, a.k.a. B.B. Pelletier
Benjamin Titan GP Nitro Piston breakbarrel puts .177 pellets out at up to 695 f.p.s.
This is a special report about an air rifle that can only be purchased directly from Crosman/Benjamin. It’s a Nitro Piston rifle, which is Crosman’s trademarked name for their gas spring, and this rifle has been limited to velocities under 695 f.p.s. The box says it’s a hunting air rifle, but I wouldn’t recommend it for that.
When one of our readers mentioned that this gun existed, I became excited because I liked the performance of the Crosman Titan GP (Lower Velocity). I did a complete report on the lower velocity Titan GP in .22 caliber. It was relatively easy to cock (for a gun with a gas spring) and had a wonderful firing behavior. It was also reasonably accurate. Those are all the things we look for in spring guns, so at the time I wondered if Crosman would ever release a .177 version of the rifle.
The gun I’m testing for you today is that airgun — a .177-caliber Titan GP with Nitro Piston that has been limited to no more than 695 f.p.s. for Illinois state law compliance. (That law has since been lifted, so these guns are being sold off by Crosman.) This is what I have been asking for, for a long time. Now I have the opportunity to test one and see what it can do.
The Titan GP is a breakbarrel spring rifle that has a Nitro Piston gas spring in place of a conventional coiled steel mainspring. That does several things for the gun. First, it lightens it by close to a pound. This test rifle weighs 8 lbs., 2 oz. with the scope mounted. I weighed it that way because there are no other sights, and the scope is essential. That puts this right in the medium weight range for a springer.
Next, the Nitro Piston makes the gun cock differently, and this is why I’ve been wanting a lower-powered .177-caliber gas spring gun to test. Conventional gas spring rifles are all hard to cock because the full force of the gas is encountered at the start of the cocking stroke — when the cocking linkage provides the least amount of mechanical advantage. When a gas spring gun cocks with 35 lbs. of force, it feels like 50 because of how difficult it is in the beginning. But the test rifle is set to deliver much lower power, which means the Nitro Piston in this rifle doesn’t require as much effort to cock. That turns out to be a great advantage when you actually use the gun.
The Titan GP has an articulated cocking link, so the cocking slot in the stock is shorter than it would have to be if the link was one piece. That helps with vibration, as well, since there’s more solid wood in the stock. I also notice the pivot bolt is slotted. That means the owner can adjust the pivot tension as required. That’s a wonderful feature, especially on a gun for this price.
The rifle is housed in a hardwood stock that’s finished with a dull sheen. The wood is not too carefully shaped, and you can see evidence of power tools used to do the shaping here and there. The wood has a very tight grain that doesn’t stand out in any way. The stock is a stylized thumbhole that I don’t care for because you’re forced to keep the thumb of your shooting hand wrapped around the pistol grip instead of along the side of the stock. It’s a clumsy feeling for me; but if you aren’t used to the older way of holding a rifle stock, it may suit you fine. I know that thumbhole stocks do have a lot of proponents.
The stock isn’t too thick through either the wrist or the forearm. It feels about the same as a Beeman R9, which is a medium-sized spring rifle.
The metal parts are finished to a dull sheen, also. They’re uniform and give the rifle the look of a hunting gun.
This is a full-sized rifle, if not a heavy one. The barrel, including the muzzlebrake, measures 18-7/8 inches long, and the overall length is 43-7/8 inches. The pull is 13-7/8 inches long.
There are no sights, so this one is meant to be scoped. Indeed a basic Centerpoint 4×32 scope and mount comes packed with it. I mounted the scope immediately because it’s the only way to sight when shooting.
So the story is — here’s a lower-powered .177 breakbarrel air rifle with a gas spring. Oh, and Crosman is selling them directly for just $71! There — have I got your attention? That was what also attracted me when our reader pointed it out. This is not a magnum springer that doubles as a portable gym. It’s a tractable, lightweight .177 rifle that could be used for plinking if you like, and as far as I’m concerned there are not enough of those on the market today.
The trigger on this rifle is supposed to be adjustable for the length of the second-stage pull via a screw located behind the trigger blade. Well, I turned that screw in both directions a LOT and nothing happened. The second-stage pull is extremely long and creepy and will have an effect on accuracy, I’m sure.
There is a safety, and I’m glad to report that it is manual. Take it off and shoot the rifle without worrying about the safety every time the gun is cocked. That’s a huge plus, in my opinion.
I have questions
First, is this rifle a suitable first air rifle? If this test proves out then it will be strong support that the market needs more rifles like this.
Second, can this rifle be accurate with the trigger that’s on it? The pull is so long, heavy and creepy that I really don’t think it can, but that’s what this test will discover.
Observations so far
I was very curious about the firing behavior of this rifle; so, as soon as it arrived, I took it out of the box and shot it several times. So far, I can tell you that it does cock easily, though not as easily as a Bronco. But for a gas spring, this is about as easy as they get.
The firing behavior is very smooth, although the rifle does lunge forward quickly at the end of the shot. Of course that is the case with all gas-spring powerplants, but this one lacks the slide-hammer effect of too much power.
The scope appears to be pretty nice for what it is. I find myself comparing it to a vintage American-made Leupold M8 scope I have that is also 4X, and this one is coming out okay.
Every so often there are deals that pop up for a while. I have made you aware of some of them in this blog, and I think the test rifle might be another one. I will therefore put it on the fast track, so you can get in line if it proves to be good.
by Tom Gaylord, a.k.a. B.B. Pelletier
I usually have a handle on the gun by the time Part 4 rolls around. But, today, I’m still stymied by the Tech Force M12 breakbarrel. I’ll tell you all I’ve done to make sure this rifle is on the beam; but when I tell you my results, I think you’ll see I’m not there yet.
I discovered in Part 3 that the M12 I’m testing is a big drooper. That means it shoots very low relative to where the scope is looking. For today’s test, I installed a B-Square adjustable scope mount that has a huge downward angle to bring the point of impact back up to the aim point. It worked well enough for the test, so I proceeded to shoot several different types of pellets — trying all kinds of hand holds and even resting the rifle directly on the sandbag.
Here’s a list of the pellets I tried: (10-shot groups with each)
Beeman Kodiak Hollowpoints
Crosman Premier 10.5-grain
Crosman Premier 7.9-grain
JSB Exact RS
JSB Exact 8.4-grain
JSB Exact 10.3-grain
Beeman Trophy (an obsolete domed pellet)
Eley Wasp (an obsolete domed pellet)
With most of these pellets, the rifle teased me with several pellets in the same hole — but a 10-shot group that was 1.5 inches and larger. A couple were all over the place and simply would not group at all. The Hobbys were probably the worst.
Only one pellet put 10 shots into 1.038 inches at 25 yards. Those were RWS Superdomes, and the hold was with my off hand back by the triggerguard, leaving the rifle very muzzle-heavy. The rifle was somewhat twitchy but not overly so.
The encouraging thing about this group is that I didn’t have to use a lot of technique to shoot it. I know it isn’t as tight as others I’ve shot at the same distance, and you’ll compare it to them, but I compared it to the other groups I was getting with this rifle. In that comparison, this was the best one and it was also relatively easy to shoot.
What all did I do?
For the record, here’s a list of all the things I tried to get the M12 to shoot.
Cleaned the barrel
Tightened the stock screws (they were tight)
Installed a drooper mount with a lot of down angle
Tightened the scope mount screws (and they were loose on the B-Square adjustable mount!)
Tried resting the forearm of the rifle:
On my open palm in front of the triggerguard
On my open palm under the cocking slot
Directly on the sandbag
Tried shaking the barrel to test the breech lockup (it is tight)
Tried extra relaxation with the artillery hold — which worked for a few shots, but never more than four
Tried attaching an extra weight to the barrel during each shot (with a large magnet)
So, where are we in this test?
I still think the M12 can shoot because there’s evidence of it wanting to stack its pellets. It might be that this is a rifle that needs more than a thousand shots to break in. I’ve owned a few of those. The Beeman C1 from Webley that I used to own was such a rifle. At first it was a royal beast; but as the shot count passed 2,000, the rifle began smoothing out and transforming into something very delightful to shoot. By 4,000 shots, the trigger was very nice and the gun had no vibration to speak of. It was this very rifle that caused me to give the artillery hold its name, and I wrote the first article I ever wrote about airguns for Dr. Beeman. He didn’t respond to my submission, so I saved it and eventually wrote it up in The Airgun Letter.
I wonder if this M12 needs that kind of break-in? That’s something I haven’t done in a good many years because it takes so much of my time. But it might be interesting to see if the rifle responds to a long-term break-in. I think I’ve certainly shoot 250-300 shots at this point, because I also tested the gun at 10 meters and one time at 25 yards (it wasn’t reported). Maybe I’ll rack up some more shots to see how that affects a longer-term break-in.
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, we’ll learn an important lesson in spring-gun management. This report was supposed to happen yesterday, but the rifle wasn’t cooperating — and I had to spend an extra day testing it. I’ll explain what haoppened and tell you what I did to fix it. It was simple, and the results are astounding. But, I’m getting ahead of myself.
As you know, I elected to test the .177-caliber Tech Force M12 4-12×40AO air rifle combo. I chose the package that came without the illuminated reticle but with the best scope.
I mounted the scope with no difficulties. The two-piece rings went on the rails easily and the rifle’s end cap was used to block the rear ring from moving during shooting. I can tell you at this point that you have nothing to fear using the cap this way. The end cap holds the ring positively and doesn’t seem to move.
Trouble in paradise!
But at 25 yards, I found I had difficulty shooting a group that was reasonable. The best I managed to do was 10 shots in an inch and a half, but I also had some that went two inches. It was discouraging, to say the least. I sat back and examined the groups to see what could be learned.
And one thing popped out. Each group of 10 was actually two very tight groups of pellets. There was enough dispersion that at first they just looked like a large group; but since I’d seen every shot go through the target and I remembered them going from one side to the other, I was able to see that there were actually two separate groups. And you know what that means, don’t you?
Let’s look at this from a different perspective. Let’s say a new reader wrote a comment and complained about the lack of accuracy in his new rifle. We might have to go back and forth several times before he mentioned that there are really two smaller sub-groups in the one group he shoots. But that would be the key that triggers a response.
Many of you would advise this reader to remove the scope from his gun and shoot a group with open sights. That’s what I would do. Only in the case of this rifle, there are no open sights. What do you do then?
There is a “secret.” It really isn’t a secret; but from experience, I’ve found that only a few people know about it.
The secret is this: When you get multiple groups like this, the problem is usually caused by a floating erector tube inside the scope, assuming that all the mounting screws are tight. And in this case, I checked them and all were tight. The stock screws were also tight. So the erector tube is the suspect. The thing that sets it up to move like that is when the scope is adjusted up too high or too far to the right, so the erector tube spring (the spring that pushes against both adjustment knobs) has relaxed to the point that the tube can move. It’s a common fault when using a scope, and I’ve been seeing it more and more often with firearms, too.
What I would tell a new reader is to crank a LOT of down elevation (at least 60 clicks — more is better) into his scope and shoot a group. I don’t care that the pellet is now striking the target low. What I care about is the size and shape of the group. That’s exactly what I did. I cranked in 5 or 6 full rotations of down elevation into the scope.
Because the rifle was now shooting very low, I decided to test the rifle at 10 meters just to keep the shots on the paper. I’m not going to tell you the pellets that were tried at 25 yards because what follows explains why they were not tested fairly.
The first pellet I tried in this experiment was the 10.3-grain JSB Exact dome. Inside of 3 shots, I knew I’d found the problem and was fixing it. The 10-shot group I got is not that small for just 10 meters, but it was relatively easy to shoot, meaning that I did not have to use more than the usual amount of artillery hold technique.
Next, I tried Crosman Premier heavies, thinking that the rifle was going to lay them in no matter what it was fed. But not this time. When 4 shots gave me almost 1.5 inches, I stopped! Clearly, this 10.5-grain dome is not the pellet for the M12.
Then, I tried a pellet that has never worked in any test I’ve done. The Beeman Trophy pellets I have are so old that they come in the old-style Beeman tin. But, I thought, what the heck — this is just a test. Let’s see what they can do. And, of course, they were stunning. Ten made a group that measures 0.458 inches, but 8 of those 10 shots made a 0.253-inch group that’s very round and encouraging.
Not only did the Trophy pellet make a nice round group, it also required very little special shooting technique. The gun felt like it was in the zone with this pellet.
I have to say this 4-12×40AO Tech Force scope that came with the rifle is a pretty nice optic for being included in a combo package. It focuses clearly and seems bright enough for general use. Once I found the problem, this scope performed as well as any scope would under similar circumstances. If you plan to purchase an M12, I would recommend getting it the way you see here.
Where are we with the Tech Force M12?
Obviously, I haven’t finished the test of the M12. I still need to shoot the rifle at 25 yards to see how well it does. And I know the groups are going to be larger than what you see here. Before I do that, I need to mount this scope in a good drooper mount so I can get the gun shooting to the point of aim, again.
Today’s report is a valuable lesson in what to do when you’re having problems getting a scope to work. The diagnostic for this is when the rifle wants to shoot several groups that are each respectable; but when taken together, they’re too large. In the situation I’ve shown here, we didn’t know if the problem was the rifle, the scope or something else. By dialing in a lot of down elevation and sometimes some left elevation, we put tension on the erector tube springs, taking them out of the equation. If the gun then shoots well, as this M12 clearly did, then you know you have a droop problem that’s easy to solve.
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, we’ll look at the firing behavior and velocity of the Tech Force M12. You readers had mixed feelings about this rifle. Some of you liked the look of the gun and the fact that the trigger is nice, though it’s only single-stage. Others were put off by the lack of open sights. Once again, for anyone who missed it, the Tech Force M12 is made for Air Venturi (who owns the Tech Force name) by Mendoza. It is not a model Mendoza makes under any other name, so if you want one, you have to get an M12.
I’m testing the combo with the 4-12×40AO Tech Force rifle scope. The scope comes into play in the next report, when I look at the rifle’s accuracy. Now, we’ll look at its performance over the chronograph. The first pellet I shot was the one I think may shoot best in the rifle — the venerable Crosman Premier 7.9-grain dome.
The first several shots from the rifle detonated, which means they were accompanied by a loud bang. Some people call that dieseling, but it’s more than that. Dieseling means that the piston causes the oil in the compression chamber to ignite when the gun fires. All spring guns in this power class diesel with every shot — even the ones that have been tuned. You don’t usually notice it because there’s so little oil to act as fuel for each shot that the gun neither makes a bang nor does it smoke. Only when there’s too much oil does the gun smoke with every shot, and only when there’s even more oil does it detonate. Detonation usually goes away after one to several shots, so you just keep shooting until the gun becomes quieter.
The M12 only detonated on the first 4 shots with Premier lites. The first shot went 1012 f.p.s., which is well over the advertised velocity of 750 f.p.s. for lead pellets. It was the detonation that caused the higher velocity, because shot No. 2 went 932 f.p.s., even though the rifle was still detonating.
After 7 shots, the rifle had stabilized, and the velocity had dropped to the 800 f.p.s. mark, which is what we expect it to do with this pellet. The average velocity was 797 f.p.s., and the spread ranged from 792 to 800 f.p.s. That’s a tight 8 foot-second range that tells me the Premier lite will probably be a good pellet for the accuracy test. At the average velocity, this pellet generates 11.15 foot-pounds of muzzle energy.
The next pellet I tested was the RWS Hobby — an all-lead pellet that weighs 7 grains. I use Hobbys or other RWS pellets of equivalent weight to test spring guns for power, so we can have a standard reference.
Hobbys averaged 848 f.p.s. in the M12, but their performance was not stable. They ranged from 829 to 877 f.p.s. While I did not hear any definite detonations while shooting Hobbys, there was a lot of smoke with each shot, so the rifle is still burning off oil. It’s good to get that out of the way now before the accuracy test, where it would disturb the shots. At the average velocity, Hobbys produced 11.18 foot-pounds of energy at the muzzle.
The next pellet I tested was the 10.3-grain JSB Exact dome. I felt that a heavier pellet might help stabilize the rifle in the early stages of its break-in. This pellet averaged 716 f.p.s.; but like the Hobbys, it wasn’t too stable. The spread went from 699 to 746 f.p.s. At the average velocity, this pellet generated 11.73 foot-pounds — the highest power noted in this test.
And the last pellet tested was the lead-free RWS HyperMAX pointed pellet that weighs 5.2 grains. These averaged 961 f.p.s. in the test rifle if I throw out the first shot that registered 919 f.p.s. The spread of the average string ranged from 948 to 970 f.p.s., so once more it wasn’t too stable. At the average velocity, this pellet produced 10.67 foot-pounds of muzzle energy.
The M12 has surprised me thus far. Why? Because it’s a Mendoza, a company that I know can make some wonderful air rifles. But they often add too much oil during assembly. The M12 is not like that. Yes, it does have a little too much oil, but the same can be said of a new Weihrauch these days. And Air Venturi had them eliminate the oil hole they put on all their rifles, so there’s no encouragement to continue over-oiling the gun.
It seems well-behaved. The oil takes care of itself during the break-in period, so it’s of no consequence. The trigger is still very nice, though I can now feel it moving through the single stage. But there’s still no creep and it still releases crisply. The trigger breaks at 2 lbs., 15 oz. fairly consistently.
The firing behavior is accompanied by a slow shudder, not by high-speed vibration, so this rifle will probably be pleasant to shoot. The trigger is good enough to do good work on target, and I think the rest remains to be discovered.