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Tenex

The TOPS-20 operating system by DEC was the second proprietary OS for the PDP-10. It was preferred by most PDP-10 hackers over TOPS-10 (at least by those who were not ITS or WAITS partisans). TOPS-20 began in 1969 as Bolt, Beranek and Newman's TENEX operating system, using special paging hardware. The system is entirely unrelated to the similarily-named TOPS-10. more...

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TENEX

In the 1960's BBN was involved in a number of LISP-based artificial intelligence projects for DARPA, many of which had very large (for the era) memory requirements. One solution to this problem was to add paging software to the LISP language, allowing to write out unused portions of memory to disk for later recall if needed. One such system had been developed for the PDP-1 at MIT by Dan Murphy before he joined BBN. Early DEC machines were based on an 18-bit word, allowing addresses to encode for a 262kword memory. The machines were based on expensive core memory and included nowhere near the required amount. The pager used the otherwise unused bits of the address to store a key into a table of blocks on a magnetic drum that acted as the pager's backing store, and the software would fetch the pages if needed and then re-write the address to point to the proper area of RAM.

In 1964 DEC announced the PDP-6. DEC was still heavily involved with MIT's AI Lab, and many feature requests from the LISP hackers were moved into this machine. BBN became interested in buying one for their AI work when they became available, but wanted DEC to add a hardware version of Murphy's pager directly into the system. With such an addition, every program on the system would have paging support invisibly, making it much easier to do any sort of programming on the machine. DEC was initially interested, but soon (1966) announced they were in fact dropping the PDP-6 and concentrating solely on their smaller 18-bit and new 16-bit lines. The PDP-6 was expensive and complex, and had not sold well for these reasons.

It wasn't long until it became clear that DEC was once again entering the 36-bit business with what would become the PDP-10. BBN started talks with DEC to get a paging subsystem in the new machine, then known by its CPU name, the KA-10. DEC was not terribly interested. One development of these talks was the inclusion of two dual memory areas, allowing all programs to be divided into a protected (exec in DEC-speak) and user side. Additionally, DEC was firm on keeping the cost of the machine as low as possible, including only 16k words of core and placing registers in RAM, resulting in a considerable performance hit.

BBN nevertheless went ahead with its purchase of several PDP-10s, and decided to build their own hardware pager. During this period a debate began on what operating system to run on the new machines. Strong arguments were made for the continued use of TOPS-10, in order to keep their existing software running with minimum effort. This would require a re-write of TOPS to support the paging system, and this seemed like a major problem. At the same time, TOPS did not support a number of features the developers wanted. In the end they decided to make a new system, but include an emulation library that would allow it to run existing TOPS-10 software with minor effort.

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Target lite: the Beretta 87 Target is a sleek, flat, smooth to run and sweet to shoot, elegant little .22 pistol
From Guns Magazine, 11/1/05 by Massad Ayoob

Many handgunners feel the need to fill a niche occupied from 1915 through 1977 by the magnificent Colt Woodsman .22 pistol. There was nary a gun expert with a bad word to say about it. Askins, Keith, Cooper, Grennell, Lachuk, et al raved about it. The Woodsman's slim profile lent itself to tucking in the waistband for a walk in the woods. Match target-grade accuracy was combined with superb fit in the hand, the quality of a Rolex watch and, of course, it was fun to shoot.

The Woodsman has been out of production for more than a quarter century. Many have striven to assume its mantle. Some have been too fat, too bulky, too clunky, or too inaccurate to be a successful pretender to the throne. But one of the few that does meet those five criteria--slimness, accuracy, fit, quality, and "fun factor"--is a little known pistol from Beretta, the Model 87 Target.

Unpretentious History

Beretta has made .22 Long Rifle sport pistols for years. One of their late, lamented classics is the slender, stylish Model 70, bought in large numbers by Mossad, the Israeli Secret Service, and in itself a contender for the Woodsman's vacated throne at one time. The Series 70 was replaced by the Model 87. Here's how I explained it in The Gun Digest Book of Beretta Pistols, soon to be published by Krause.

"Beretta introduced the Cheetah Model 87 in 1988. It was a companion gun to the Model 84 and Model 85 series .380s, and was functionally identical except for being chambered for the .22 Long Rifle cartridge. The same yeas the firm offered the Model 89 Gold Standard, an aptly named target pistol that was built on the same frame but in single action only mode, with a skeletonized slide running under a high sight-ribbed barrel. The Gold Standard came with an exquisite target grade trigger pull.

"Along about 2000, the Model 89 Gold Standard seemed to disappear from the line, replaced by the Model 87 Target. Where the Gold Standard had resembled a cross between a Cheetah .380 and a Hammerli match pistol, the 87 appeared to be a Cheetah frame with the trigger squared a little in front, and a barrel/slide assembly that was in essence the one from the Gold Standard, but trimmed down a bit from the top and with a Weaver-style scope rail that also acted as a low-profile (iron) sight rail. The Model 87 Target pistol has its own ten-shot .22 LR magazine and will not accept the seven-round mag of the .22 caliber Model 87 Cheetah."

In The Hand

The 87 Target feels lighter in the hand than its stated weight of 41 ounces. Give it five stars for that subjective category of "feel." Having been cloned from a "pocket pistol" design, it's a small-frame gun and allows easy reach to the trigger, even for those with very short fingers. The checkering is just fight on its plastic grip panels, which neither abrade nor slip in the hand. The trigger rolls back smoothly, with an easy surprise break that reminds you of the best commercial 1934 series .380s, and that great old Beretta 70 .22. That "roller release" is conducive to good shooting.

Because of the overhead sight rail, the slide has no grasping grooves in the rear. The serrations are up front. It is designed for you to bring the support hand up under the frame, ahead of the triggerguard, but of course well behind the muzzle, and work the slide with thumb and forefinger, for which handy serrations are in place. I don't much care for this handling mode in most semiautomatic pistols, but it's almost necessary when you have the sight rail blocking hand access to the rear of the slide.

The rail is one element of the pistol's accuracy, which as we shall see, is extraordinary. As with the S&W Model 41 and the High Standard Victor before it, its design is a recognition of the fact the sights and barrel have to be in continuous, perfect alignment. The accuracy variations in most semiautomatic pistols are largely a function of the sight-bearing slide returning to a subtly different position vis-a-vis the barrel, what is called "being in battery." When the sights are affixed to the barrel, as by this rail (or the barrel with its front sight and the receiver with its rear sight, as on the Ruger .22 auto, are rigidly attached to one another) play is minimized and, therefore, accuracy is maximized.

Old World Craftsmanship

Made in Italy by the craftsmen of the world's oldest gun manufacturer, these sleek .22s have the same smooth action feel of the Model 92 service pistol or one of Beretta's sweet over/under shotguns. The slide glides back and forth on the frame as if on ball bearings. With the little protruding nubs of the follower caught by your fingernails, its open-side 10-round magazine doesn't fight you when you insert the cartridges. The pistol comes with a slimmer replacement front sight, which locks in via a nut above the muzzle, a removable front-end weight and Allen wrenches to allow you to remove either. There's also a spare magazine.

This is a single-action pistol. Those who don't have very strong hands will find the from-the-front slide jacking is easier if the free hand cocks the hammer first, relieving mainspring pressure. The frame-mounted safety works in the directions American handgunners are habituated--up for safe, down for fire--and with just the right amount of resistance to the thumb.

Trigger

Good news and bad news with the trigger. Good is the surprise rolling let-off and a 4.5-pound pull just right for use in the field (as opposed to the tournament range). Bad is the worst over-travel I have seen in 46 years of shooting .22 caliber semiautomatic pistols.

Backlash, the rearward movement of the trigger after sear release, was horrendous. Just before the trigger slammed into the back of the triggerguard window, it paused long enough to drag a line through the handsome bluing inside the bottom of the triggerguard. The result was the 25-yard groups are bigger than they should have been, though analyzing the best three out of five hits indicated that this gun had some great but unrealized accuracy potential.

My friend Jeff Brooks had run into the same thing when he bought an 87 Target for his young son Jonathan. He wrote me, "Trigger overtravel is absolutely horrible and very excessive," and asked if I could recommend a pistolsmith. I steered him toward Teddy Jacobson at "Actions by T" in Sugarland, Texas. The results were as expected, and Jeff soon wrote back that Jonathan was kicking butt with the Beretta since the trigger work. "We love the 87 Target," he told me. "Teddy Jacobson did an outstanding job on trigger pull-weight, smoothness, and travel."

However, since this gun belonged to Beretta, I couldn't justify doing any custom work on it. My buddy, Jon Strayer, is a mechanical genius and came to the rescue.

His answer was a small piece of floor protector, the adhesive-backed heavy-duty cushion designed for the bottoms of table and chair legs to keep them from scuffing floors. He cut it to fit and stuck it in the back of the triggerguard.

Great Accuracy

And that was it. With the backlash gone, the 4.5-pound pull-weight presented no problem. The first five-shot group fired thereafter with CCI Pistol Match ammo went into .95" at 25 yards, the best three shots in about 0.35".

Anything that puts every shot under an inch at 25 yards is at the "gold standard" of handgun accuracy. However, there are those who seek a "platinum standard." They're the kind of folks who win at the National Championships hosted at Camp Perry, and they're satisfied with nothing less than 1.5" at 50 yards. The hell of it is, it looks like this pistol can deliver that, too.

In the months since I sent the Beretta book manuscript to Krause, my friends and I have been playing with this gun. (Yes, I bought it.) The best group I've seen it produce so far is 0.65". I haven't been able to repeat that, but I suspect that has more to do with me than with the pistol. The best three shots on that particular target, with two in one hole, were about a quarter inch apart.

A friend and fellow writer got astounding accuracy out of his Beretta 87 Target. He put a Burris 2-7X handgun scope on the Weaver rail, presumably cranked up the magnification, set up on the sandbags 50 yards from the target and proceeded to shoot 2" groups or better with a dozen different loads. He reported that two of those, Eley Tenex 40 grain and Wolf Match Gold 40 grain, did under an inch at those 50 paces: .87" and .67", respectively. (1) That's simply phenomenal accuracy.

This 87 Target shoots its best with match-grade, standard-velocity ammo, but this one can still give champagne performance on a beer budget. I went to the bench with a couple of popular field loads. Remington's mass-market "Golden Bullet" high speed solid did 1.10" for five shots at 25 yards, with the best three hits in 0.55", as usual measuring to the nearest .05". Winchester's garden variety high-speed hollowpoint, a popular small game load, did 1.30" for all five at the same distance and put its best three in .90", with two shots through one hole.

Reliability

As I said of this gun in the Beretta book, "... my test 87 Target did not malf once. My friends and I all liked the way this little pistol was set up, and a bunch of. us have put a bunch of ammo through it. Not enough bricks to build a house, but enough bricks of .22 ammo to know that (this) Beretta Model 87 Target ... is an extraordinarily reliable little pistol."

A few more bricks have gone through it since. It still hasn't malfunctioned. I'm guessing cleaning occurred about every 1,000 rounds.

Weights And Such

The barrel weight doesn't weigh that much but hanging down at the front of the gun it makes an otherwise slim and graceful pistol feel a tad muzzle heavy. I took it off, and it made the gun "feel more lively." I think I like it better that way. The barrel weight is tough to pull off and just about needs to be hammered back on (with a soft mallet, of course), but keeping it on or slipping it off is up to you. I could detect no difference in accuracy with or without the barrel weight in place.

This gun's unique profile will require either a custom made holster or a generic "one-size-fits-several" variety. Though it lacks the double action capability of the rest of the Cheetah series, it has a similar feel and thus makes a good "understudy gun" for those who carry an 80-series Beretta .380 for self defense. My predecessor as handgun editor at GUNS, Jan Stevenson, was the one who coined the term "understudy gun" for a .22 caliber version of one's defensive pistol, and I would fail to carry on that legacy if I didn't mention that the standard Model 87 .22 in double action with conventional slide will be better for pure defensive practice, and will also replicate the Model 85 or Model 84's profile in the same holster. However, the standard 87 can't be expected to deliver the gilt-edged accuracy built into the Target model.

I would like to see Beretta bring back the more precisely adjustable trigger of the Gold Standard but, I'd be satisfied with the neat little trigger stop they used to put on their .380s in the same series. In the meantime, the 87 Target owner will not be sorry if he follows the example of Jeff Brooks and sends the pistol to Teddy Jacobson for a complete trigger job.

Bottom Line

Reading all the nitpicking above, it sounds as if I don't like the gun, but I do. You sometimes find the most faults with the things you care most about. The fact is, the Beretta 87 Target is a heckuva gun. It's roughly twice the price of a comparably equipped Neos, the "plastic" Beretta .22, but I think it's more than twice the gun. Far more accurate, more "shootable" in many respects, and with vastly more of the old-world artistry in metal that has made q-u-a-l-i-t-y an optional spelling for B-e-r-e-t-t-a. Heck, I bought it, didn't I?

Notes: (1) "Beretta's Model 87 Target is a Rimfire Masterpiece," by David M. Fortier, 2005 Shooting Times Handgun Buyers' Guide, Primedia.

COPYRIGHT 2005 Publishers' Development Corporation
COPYRIGHT 2005 Gale Group

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