Which QB78 Parts Fit My Crosman 160?

We're often asked this question here at Archer Airguns!

The answer is that many QB78 parts do, in fact, fit the Crosman 160, and also the Crosman 167, Crosman 180 and Crosman 400 models. We publish a list of individual part compatability at http://www.archerairguns.com/crosman-160-airgun-parts-s/24.htm and also list the main parts kits that are available to keep these classic American air rifles in service.

And how to fit them? That's where our QB78 Family Workshop Manual comes in.

This unique 88-page publication gives the information required to make repairs not only to the QB78 family, but also the Crosman 160. The Crosman 167 and 180 models are very similar and can also be repaired using these instructions as a base.

The Crosman 400 is, however, a completely different issue. It's a far more complex air rifle due to the magazine system and we recommend professional repairs for that reason, even though some of the QB78 parts will fit that fine airgun.

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The AR2095. The Air Rifle That Never Was.

For several years, the Shanghai Airgun Factory had showed a new PCP air rifle on their website, in catalogs and at the SHOT Show. This model - the AR2095 - has never made it to production and has become something of a mythical beast. But there is one example in captivity and we’ll see it in this blog post.

The owner of the Shanghai Airgun Factory sent me a prototype AR2095 back in 2007 and asked for my opinions. I was, of course, happy to help and provided the requested input. Unfortunately it was not too complimentary. Maybe my view was shared as the AR2095 has never made it to production and has now disappeared from the company’s catalog.

I’ve never shared details of this air rifle before, but here it is in public for the first time.

This AR2095 weighs 6lb 13oz without an air tank and has an overall length of 40.5 inches. The pull length is 15 inches.



The side lever breech mechanism is not unusual for Shanghai as they have used this concept before in the rarely-seen AR2078B and AR2079B models. But probably the most contentious feature to me was the removable air tank concept. The idea was good, but it was - in my view - unnecessarily compromised - by trying to make it also “built in” to the gun. I would have preferred either a built-in fixed tank, as the BAM B50 or an entirely separate tank in QB79 style.

What do you think? Should they have introduced this PCP air rifle?

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QB57 Performance Review. Part 2 - Accuracy and trigger Pull

This is my own cutomised QB78, with a re-finished and extended stock, muzzle brake and other modifications.

Here’s some more, never previously published, “hard data” on the performance of the QB57 air rifle from Shanghai Airguns. It’s derived directly from Archer Airguns “Gold Service” testing of these guns and summarises results from a large number of tested guns.

Part 1 covered muzzle velocity testing. In this second part we’ll cover accuracy and trigger pull results.

The factory spec for accuracy is a grouping of 30mm - that’s 1.2 inches - CTC (center to center) at 10m (32 feet) for just 3 shots. This spec is not impressive (in fact it’s terrible), but performance is hugely better in practice. In “Gold Service” testing, we see an average CTC of around 0.6 inches for 10 shots at 10 yards - 2X better than the factory spec - as this chart shows.

This compares very well with the tested accuracy of QB78 family air rifles - it’s about the same CTC as “Gold Service” testing produces with these accurate CO2 guns. And I’m emphatically NOT a good shot with a springer, I just can’t manage a completely consistent hold time-after-time, so good spring rifle shots using pellets the gun “likes” will undoubtedly be able to improve on my accuracy results.

Average accuracy is slightly better for .177s over .22s (just as with the QB78 family), but there’s actually very little in it. It’s too close to call without an even larger population of guns to test. Just give me more time, I’m working on it...

Most of these accuracy results are obtained using a basic Leapers red/green dot scope. Where customers specify our QB57/Leapers Scope Combo, the test results were achieved with that combination. I’ve not differentiated between sighting options in this graph, but you can understand that most of the “tight” groups were sighted with the 4 x 40 scope.

As I measure CTC only to the nearest 1/8-inch, that accounts for the steps in the graph. But, as you can see, here we have an accurate little air rifle!

The QB57 has a long, creepy trigger pull - as you might expect from a cheap bullpup-style air rifle. But it’s actually not that bad and is surprisingly light and consistent. There’s also an adjustment screw, but I never touch that so this data represents completely “stock” trigger performance.

The factory spec provides a very generous range from a maximum pull weight of 5 lbs 10 oz (itself not unusual in a cheap spring-powered air rifle) down to a minimum of 2 lbs 4 oz. But the actual results are much better and are shown in this chart.

The good news is that trigger pull weights are all very close to the minimum factory spec and - as you can see - a reasonable average figure is around 3.0 lbs. Again, a very good performance for such a low cost air rifle. And the trigger is adjustable via a setscrew, so there’s the potential to improve these pull weights beyond the stock factory settings.

So, that’s the QB57! It’s an unique little air rifle and the performance is really very good for such a low cost air rifle. And - being made of real “tree wood” and steel, there’s much potential for tuning and customisation.

I hope that you’ve enjoyed this review of the QB57. Try one, you may find it a lot of fun :-)

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QB 57 Performance Review. Part 1 - Muzzle Velocity and Dieseling.

The QB57 is this interesting take down air rifle from China manufactured by the Shanghai Airgun Factory and sold by Archer Airguns.

I like the QB57 a lot - it’s a fun gun to shoot, unusual-looking and is quite hold-tolerant for a spring air rifle. And although I am the first to agree that the finish and appearance of the QB57 is not among the best, it really shoots well. But how well?

To answer that question, I’ve analysed the results of Archer Airguns “Gold Service” testing for a large number of QB57s and graphed the results for easier understanding. To my knowledge, this blog contains the first comprehensive performance analysis of “hard data” that has ever been published for the QB57. Here’s what I found...

Overall, the QB57 significantly improves on the manufacturer’s specifications and performs very well for an air rifle in this price range.

First things first. Please remember that “Gold Service” testing is performed with heavy, flat-nosed wadcutter pellets, so my results will clearly be slower than for the same gun shooting light, pointed pellets.

Also, I’m always testing new guns. Some of these are “dry” from the factory, while others have their innards liberally coated in oil. (Don’t ask me why, that’s just the way they are). This is important as all spring air rifles that have oil in the compression chamber will tend to “Diesel”. Some of this oil will actually combust due to the pressure of the compressed air in the chamber - the result is increased, but erratic muzzle velocity. We will see the effects of Dieseling clearly in some of the results here.

Let’s get to the results...

Muzzle velocity for the QB57 in .177 caliber is very close to the manufacturer’s claim of 650fps. “Gold Service” testing averages about 620fps - 95% of the manufacturer’s claims: it would probably equal the claimed muzzle velocity with light, pointed pellets.

This graph shows the distribution of muzzle velocities actually recorded on test. The higher velocities - above about 660fps are real and clearly the result of Dieseling.

QB57 muzzle velocity results in .22 caliber suggest that the manufacturers have under-specified this little gun with their claim of only 480fps. As you can see from the graph below, I have recorded muzzle velocities of 700fps on test with Dieseling guns. That’s around 15 ft/lbs of muzzle energy from this little gun. Wow!!!

I would suggest a more realistic muzzle velocity specification in .22 to be about 560fps, that’s 15% above the manufacturer’s claims. Now this is really unusual - an air rifle that actually gives a muzzle velocity greater than is advertised!

So how does Dieseling effect muzzle velocity consistency?

Well, consistency is expressed mathematically as “Standard Deviation”. Basically, a low standard deviation figure is good - it means that the shots are all of a similar muzzle velocity. A high number indicates considerable inconsistency and is, therefore, bad.

As we said, Dieseling effects all spring guns - not just the QB57. But the graph below clearly shows its impact.

“Dry” QB57s have a standard deviation of below about 10 fps in “Gold Service” testing. Compare this to an average for QB78s of around 5 fps. Not bad at all.

But it’s easy to see a sharp jump in the graph - suddenly standard deviations double and then triple very rapidly. This is Dieseling in action and it’s the guns with plenty of oil that do it.

Dieseling declines as the oil burns off - any spring air rifle will dry out with time. This leads to a conclusion that the average standard deviation for a “dry” QB57 is well below 10fps. Let’s say somewhere between 5 and 7 fps. This is very creditable for such a low cost spring air rifle.

But wait, there’s more... and it will be published in Part 2 of this review.

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The Crosman 760 - a Review

Crosman claims that over 12 million of these little air rifles have been sold during an continuous production run starting in 1964 - that’s well over a quarter a million a year for 45 years - so they must be doing something right with their Crosman 160!

To find out, I did what most people do. I went to Wal-Mart and walked out with one under my arm for the princely sum of $29 plus tax. But then I decided to do what most people don’t : I gave the Crosman 760 an Archer Airguns “Gold Service” test to find out what performance it produces. I also tested it with four different types of pellets to see how pellet sensitive this 760 is.

Crosman claims a muzzle velocity of up to 600 fps with pellets for the 760. I’m here to tell you that my Crosman 760 achieves nothing close to that with lead pellets - it’s more like 500 fps. But using Crosman Silver Eagle lead-free wadcutters, my 760 did manage to average nearly 630 fps.

Amazingly, I’ve never shot a Crosman 760 before, but I here’s what I found...

The gun is overwhelmingly “plastic” to the touch - as most of the parts are made of this material. Personally I don’t like this, but it does make the 760 very light and easy to hold. It’s undoubtedly a big contributor to that sub-$30 price point, too.

Pumping was surprisingly hard and made a loud sound each time the forearm completes its stroke and hits the air tube. This actually seems louder than the sound of the 760 firing! I used 10 pumps for each shot, the maximum recommended by the manufacturer, to achieve the highest muzzle velocity.

I thought the trigger was fine. Mine pulled fairly evenly at about 3.5 pounds. And I had no jams in 50 shots (that’s 10 “warm up” rounds plus four test targets of 10 shots each). Not bad! The factory iron sights are also surprisingly good, although I used a red dot scope for the testing.

The 760 comes in a nice, brightly-printed box and the instructions are in Spanish and English. I can’t read Spanish, but the English instructions didn’t really seen ideal to me, I still needed a little experimentation to learn how to load the pellets into the clip and the clip into the 760, for example.

So how did my 760 shoot? Well, the test targets are below. I simply followed the standard Archer Airguns “Gold Service” test procedure four times with different pellets. Each test was fired with 10 pellets. And each time I called a “flyer” with one pellet that was way out of the main group. You’ll see this below. All the tests were shot using my trusty Leapers red/green dot sight.

First off, the standard Crosman wadcutters. Available everywhere, these shot at an average muzzle velocity of just over 480 fps, giving a muzzle energy of a little over 4 ft/lbs. Don’t hunt any bird or animal with this gun, there’s not enough power for a humane kill in my opinion. Accuracy was OK-ish. Not bad for a sub-$30 gun with an un-rifled barrel.



Next, I tested Crosman Silver Eagle wadcutter pellets. As in every gun I’ve shot these through, the muzzle velocity was excellent - 25% better than with lead pellets. The bad news? That muzzle velocity comes with even less muzzle energy (because of the light weight of the pellets) and abysmal accuracy. I can’t hit the proverbial barn door with these pellets in any air rifle.



Third was the turn of the Chinese “The Peak” pellets that we sell. These produced better accuracy and muzzle energy than the Crosman lead wadcutters, probably because they use a softer lead and have a wider “skirt”. These probably sealed better in the barrel and allowed less air to leak past the pellet than the Crosman wadcutters. They gave the highest muzzle energy at nearly 5 ft/lbs, together with fairly reasonable accuracy.




Finally I tested Crosman Premier Light pellets. These domed pellets are relatively expensive, but wow, what great accuracy! Suddenly the 760 was producing excellent accuracy, vastly better than I expected for this little air rifle. Just look at this test target!



So, the little 760 finally found a pellet it liked, and how!

Overall, I feel that you can’t complain about the Crosman 760 for $29.00. But somewhere around $70 buys a far, far, far better air rifle, such as the QB78 or QB36-1. These guns are all metal and wood and will last a lifetime, they’re more accurate and significantly more powerful, yet still easy to shoot - and they don’t need all that noisy pumping...

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