Ruger SP101 .327 Magnum Revolver

By the Guns and Shooting Online Staff

Ruger SP101
Illustration courtesy of Sturm, Ruger & Co., Inc.

Federal's announcement of the new .327 Magnum cartridge caused quite a stir at Guns and Shooting Online. Several of us have been longtime fans of the .32-20 and .32 H&R Magnum as applied to revolvers. Both are fine cartridges, but are barely hanging on in sales and few--if any--modern firearms are offered in these calibers. The advent of a new .32 caliber magnum cartridge, ballistically equivalent to the old high velocity (rifle) version of the .32-20, is right down our alley.

The new cartridge is based on a .32 H&R Magnum case lengthened by 1/8". Despite its misleading nomenclature, the .327 Federal Magnum actually uses the same .312" diameter bullets as the earlier ".32" caliber cartridges. (They are all .31 caliber cartridges in terms of actual bullet diameter.) In fact, any .327 revolver can also fire .32 H&R Mag. and .32 S&W Long/.32 Colt New Police cartridges in much the same way as a .357 Magnum revolver can shoot .38 Special cartridges.

The reverse, however, is not true. The longer .327 Federal Mag. cartridge should not fit in the shorter .32 caliber revolver chambers and even if it did, because it is loaded to much higher pressure, it would be dangerous to attempt to fire .327 cartridges in a .32 H&R Mag. or .32 Long revolver.

Federal Cartridge (a Division of ATK) introduced their new .327 Magnum at the 2008 SHOT Show. Initially, there are three factory loads offered in the caliber. One is in the Federal Premium Personal Defense Low Recoil line, an 85 grain Hydra-Shok JHP bullet at a muzzle velocity (MV) of 1400 fps with muzzle energy (ME) of 370 ft. lbs. The second is in the more economical Federal American Eagle line and drives a 100 grain jacketed soft point bullet at a MV of 1500 fps with ME of 500 ft. lbs. Speer (another ATK subsidiary) is offering the third factory load, which uses a 115 grain Gold Dot JHP bullet at a MV of 1380 fps and ME of 486 ft. lbs. These advertised ballistics were achieved in a 4" vented test barrel.

The .327 Federal Magnum is being marketed as a personal defense cartridge that hits harder than the .38 Special +P and kicks less than a .357 Magnum. It also hits about twice as hard as the .32 H&R Magnum, but kicks correspondingly harder.

That is all well and good, but the world is lousy with perfectly good, short range, self-defense cartridges. It seems to us that the real advantage of the .327 Magnum is its high velocity and flat trajectory. It can reach out beyond 100 yards and this makes it superior to all of the common centerfire revolver cartridges except the .357 Magnum, .41 Magnum and .44 Magnum. Actually, it even shoots a little flatter than that famous trio. The .327 Magnum would be a better choice for protection from two legged predators in the field than traditional self-defense numbers with rainbow trajectories like the .38 Special, .40 S&W and .45 ACP. It would also be an excellent cartridge for the handgun hunter seeking game such as jackrabbits or coyotes.

Ruger collaborated with Federal in the introduction of the .327 Magnum and the first revolver chambered for the new cartridge is the Ruger SP101. The SP 101 revolver, to paraphrase Ruger's description, is a small framed gun that can handle magnum cartridges. It features all stainless steel construction, triple-locking cylinder mechanism that securely locks the cylinder into the frame and a frame that has no side plates. Safety is provided by a transfer bar mechanism that allows the revolver to be safely carried with all six chambers loaded.

This is a compact, but rather heavy, double action revolver. It weighs some 28 ounces. A frame extension houses the SP101's mainspring spring seat and trigger guard latch. The grip frame is designed to accommodate a variety of custom grips, which is convenient since the stock grips are dysfunctional and ugly. One look and feel of the standard grip had us on the phone to Lyman/Pachmayr requesting one of their excellent Pachmayr Compact grips for the test SP101.

Like all Pachmayr grips, the Compac is easy to install and fits nicely. With most revolvers, all you have to do is to remove the single screw retaining the stock grips, remove them and replace with the Pachmayr grip. In the case of the SP101 the process is a little different, but not difficult. First, remove the screw securing the stock grip. Then, pry out the plastic inserts, taking care not to lose the small copper plated pin hidden beneath one of the inserts. This small pin has nothing to do with the grips, but is used when removing the hammer spring. Push out the large silver locator pin thus revealed. Now the stock grip can be slipped off the stub grip frame. Slide on the Pachmayr Compac grip, which eliminates the need for a locator pin and is conveniently secured by the single screw supplied.

With the Pachmayr Compac grip in place, the SP101 immediately feels better in the hand. For one thing, unlike the stock grip, it is just long enough to allow the little finger of the strong hand a place on the grip. In addition, the Compac fills the space behind the trigger guard so that the trigger and middle fingers are not crossed and the trigger guard does not rap the middle finger on recoil. The Compac's textured rubber surface provides a secure grip and feels better in the hand than the Ruger grip's deeply grooved, hard plastic inserts. Its material and shape handle recoil better, a particularly noticeable benefit when shooting snappy .327 Magnum factory loads. The SP101 with a Compac grip still fits in its supplied plastic case as well as whatever holster you choose to use. Pachmayr Compac is a substantial improvement in the function and appearance of the SP101

The hammer spur is small and sharp-edged. Its checkering is hard on the thumb and the main (hammer) spring is excessively heavy. Ruger should "melt" the edges of this hammer spur and ease the spring rates. Ditto for the trigger return spring. Gordon filed the sharp edges from his personal SP101's hammer and installed Wolfe replacement main and trigger springs and the improvement was dramatic.

The cylinder rotates counter clockwise, which is to say out of the frame. This presumably accounts for the multiple cylinder latches to keep it securely in place. Cylinder bolting is solid with very little play. The cylinder gap is tight and uniform for all chambers. The cylinder crane to frame fit is mediocre. There are noticeable, but not extreme, gaps at both the front and side. On the other hand, the trigger plate to frame fit was excellent with only a hairline visible where the two parts join.

Following are the new SP101's basic specifications.

  • Product number: KSP-32731X
  • Caliber: .327 Magnum
  • Finish: Satin stainless
  • Capacity: 6 rounds
  • Grip: Rubber with plastic insert
  • Barrel length: 3-1/16"
  • Groove and twist: 6 groove, 1:16" right hand twist
  • Overall length: 8"
  • Weight: 28 ounces
  • Sights: Ramp front, windage adj. rear
  • 2008 MSRP: $572

The SP101 is rather easily recognized by its unique frame, full-length barrel under lug, press in (rather than slide forward or back) cylinder release and stock rubber grips complete with black plastic inserts. It is not the most delicate looking revolver around, but it is probably the strongest snubby available and the top choice among currently offered models. Our sample came with a plastic case, gun lock and instruction manual.

The sights are superior to the blade front and fixed groove rear provided on most snub-nosed revolvers. The SP101 is supplied with open sights that include a low, but easily visible, ramp front sight that is pinned to the barrel and a square notch, white outline rear blade that is screw adjustable for windage. Elevation adjustment, if required, is achieved by means of a file. These sights are commendably precise and easy to align.

The double action trigger pull could not be measured by our RCBS Premium trigger pull gauge; it was off the scale. The single action trigger pull measured 5 pounds. This trigger is moderately creepy and far too heavy. Fired from a solid bench rest and a Pistol Perch, it can be managed, but it is a substantial drawback when shooting off-hand. A high velocity, hard kicking, 100-yard-plus cartridge like the .327 Magnum deserves a revolver with a clean, 2.5 pound trigger pull that lets the shooter take full advantage of its capabilities. If you are only going to use the gun at indoor ranges, you might as well get a far more common .38 Special revolver and save a bundle when you buy practice ammunition.

We were anxious to get the .327 Mag. SP101 to the Izaak Walton outdoor range south of Eugene, Oregon to give it a workout. Western Oregon's unpredictable spring weather improved a few days after the little revolver's arrival, bringing partly sunny skies, negligible breezes, and warm afternoons, so off we went.

Our friends at Federal Cartridge were kind enough to ship us a supply of Federal Premium and Speer Gold Dot ammunition for this review. (The American Eagle load was not available at the time of this review.) Their Premium Personal Defense Low Recoil load with the 85 grain Hydra-Shok JHP bullet achieves an actual MV of about 1330 fps. The Speer Gold Dot 115 grain JHP load reaches a MV of approximately 1300 fps. These figures were taken from the 3-1/16" barrel of an SP101.

Guns and Shooting Online Editor Gordon Landers owns an SP101 in .32 H&R Magnum caliber and was able to contribute a reload in that caliber for this review. Gordon's reload uses a Hornady 85 grain HP-XTP bullet with 4.0 grains of W231 powder for an approximate MV of 875 fps.

We did our firing for record from 25 yards at bullseye targets over three range sessions. We used a Pistol Perch rest on a solid shooting bench. All groups consisted of six shots with called flyers ignored. This time out, Guns and Shooting Online staffers Chuck Hawks, Gordon Landers, Rocky Hays and Jim Fleck handled the shooting chores. Here are the results.

  • .327 Speer 115 gr. Gold Dot: smallest group = 2-7/16"; largest group = 4-3/16"; mean average group size = 3.38"
  • .327 Federal 85 gr. Hydra-Shok: smallest group = 2-3/8"; largest group = 7-1/2"; mean average group size = 5.17"
  • .32 H&R Reload w/85 gr. HP-XTP: smallest group = 4-1/4"; largest group = 6-1/8"; mean average group size = 5.19"


Our range results were, frankly, disappointing. It would be reasonable to blame the shooters, except that we had three other revolvers at the range along with the .327 SP101. These included a Ruger SP101 in .32 H&R Magnum (4" barrel), a Ruger New Model Blackhawk in .45 Long Colt caliber (4-5/8" barrel) and a Colt Diamondback in .38 Special (4" barrel). All of these revolvers averaged groups about half the size of the .327 SP101's groups in the same shooters' hands. All guns are individuals, of course, so your .327 SP101 may shoot smaller groups than our test sample did. It should also be remembered that we were shooting early production ammunition, which may or may not have been a factor.

We had noticed (by reading the fine print below the test results) that when the American Rifleman magazine reviewed a .327 Mag. SP101, their bench rest groups were shot at only seven yards. (We wonder how many readers noticed that?) The very short range explains why their average group size was so much smaller than ours. Had they fired for record at the usual handgun test distance of 25 yards, their results would have been similar to ours.

Part of the problem can be attributed to the .327 SP101's heavy trigger pull, which made accurate shooting more difficult than it needed to be. This was by far the worst trigger among our four revolvers. Jim and Rocky were especially critical of the little revolver's single action trigger pull. (No one was willing to attempt to manage the SP101's horrendous double-action pull.)

Nor does the stock grip assist accurate shooting. Quite the contrary, it is so short that the little finger of the strong hand is left hanging and the grip does not fill the space behind the trigger guard. After our first range session, during which we shot with the stock grip exclusively, Rocky and Gordon complained that the trigger guard rapped the knuckle of their middle finger during recoil. (Two days later, Rocky's knuckle was still bruised.) This grip is too thin to be hand filling and the thumb notch is too abrupt in shape. The Ruger grip is practically an advertisement for a replacement grip and for subsequent range sessions, we used the Pachmayr Compac grip.

The recoil of the SP 101 shooting the Federal Premium Low Recoil load was sharp and rather unpleasant, as was the muzzle blast. It was far less enjoyable than shooting Gordon's .32 H&R Magnum reload in the same gun. The SP101/Federal Low Recoil combination also kicked noticeably harder than a Colt Diamondback revolver shooting Winchester.38 Special factory loads with 125 grain JSP bullets (MV 850 fps) that we had along for comparison. The Colt is only about one ounce heavier than the SP101, so it is a reasonable comparison.

When we test fired the full power Speer Gold Dot .327 factory loads in the SP101, the recoil became downright unpleasant. Even with the Pachmayr Compac grip and wearing a Past shooting glove, the .327's recoil with the full power Gold Dot load stings the hand. We recommend this load for experienced shooters only. Unfortunately, it was also the most accurate load in our test gun and clearly the load that the SP101 preferred.

Although considerably louder than a .38 Special +P, the muzzle blast of the .327 Mag. in the SP101 is less distracting than that of a .357 Magnum. It is a loud, sharp bang, not the violent "blam" of the larger magnums. Even so, you don't want to forget your ear protectors when you shoot the .327 SP101.

Since any .327 Federal Magnum revolver can also handle .32 H&R Magnum cartridges and the older cartridge is much more enjoyable to shoot, that would be our standard load if we owned a .327 SP101. We would reserve the more powerful .327 Mag. cartridges for special occasions.

In summation, we feel that the .327 Federal Magnum cartridge should be offered in a medium size revolver with at least a six inch barrel and a fully adjustable rear sight so that a handgunner who knows how to do so can exploit its inherent capabilities. We strongly urge Ruger to offer the .327 Mag. in either their Super Single Six (previously available in .32 H&R Mag.) or New Model Blackhawk single action revolvers. Smith & Wesson's K-frame Masterpiece revolver would also be a natural for the .327 Mag. Best of all would be a reintroduced Colt Diamondback in .327 Mag. Revolvers such as these would greatly expand the versatility of the cartridge and its appeal to hunters and recreational shooters.

This is not to say that the compact SP101 platform is not viable. It would make a good home defense revolver, particularly for women and inexperienced shooters, who should stick with .32 H&R Mag. ammunition. It would also make a neat trail or tackle box gun, a traditional "kit gun." Carried in a field holster or in a backpack, it could be a useful hiker's or camper's companion. Despite being rather heavy, it is a possible candidate for concealed carry, particularly in situations where its flat shooting cartridge might be advantageous.

One real advantage of the SP101's weight is that it helps to minimize the .327's sharp recoil. Fly weight carry revolvers, although popular right now, kick like the devil and are very difficult with which to score hits. They are comfortable to carry, but horrible to shoot. Unfortunately, in a gun fight only hits count. The SP 101 is a relatively controllable, short barreled, self-defense revolver and with factory loads available in four power levels (.32 Long, .32 H&R Mag., .327 Personal Defense Low Recoil and full power .327 Magnum), the shooter can pick the load that best suits his or her purpose and skill level.

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