C&S GP100 .357MAG

By Denis Prisbrey
Originally Printed in Combat Handguns December 2004


A while back, in the CH May 04 issue, I compared a vintage blued Ruger Security-Six .357 Magnum with a current blued GP100 .357 revolver. It was interesting to note the differences that separated the two designs by about 15 years.

The Security-Six was Ruger's first double-action revolver, engineered to be stronger and more durable than the competition's mid-frame .357s. Police requirements in the 1970s brought out both the hotter 125-grain jacketed hol- lowpoints and a more realistic training regime that had us actually qualifying with what we carried in the duty gun, instead of with light .38 Special wad- cutters, which had very little relation to either the muzzle blast or the point-of- impact of the magnum loads. Even in the Security-Six, the accelerated use of hot magnum rounds brought on accelerated wear, and the design was not cost effective to produce. The GP100 line replaced the SS in the late 1980s. The GP was beefier in critical areas of the frame, cylinder and barrel, while still holding close to the same overall size.

Shooting both four-inch guns for the write-up gave me a chance to compare performance in accuracy and handling, and left me preferring the handling and heft of the older Security-Six, but not minding the extra strength of the GP. I liked the responsiveness of the lighter barrel on my SS. It's livelier in quickly handling multiple targets and feels quite well balanced. The GPs with their much heftier barrels and full-length underbarrellug, have always struck me as being very muzzle-heavy, and just didn't balance well for me. This is pure- ly a subjective impression, and the heavier GP barrel does make a marked difference in recoil recovery. Accuracy was about the same for both guns, so that wasn't a factor in either direction. I would much like to see Ruger pro-duce a lighter, "skinny" barreled, non- underlugged version of the GP with fixed sights, but they don't, and that brings us right here.

Cylinder & Slide

Bill Laughridge's Cylinder & Slide Shop has established something of an annual tradition for me. Each year for the past four, I've sent a gun to C&S for one of their custom makeovers, and the results are four of the finest guns I own. Number Five was due, and it wasn't too long after the smoke cleared from the two-gun Ruger .357 project that the light bulb appeared over my head. Can the GP100 be improved a bit? An email to C&S brought a return message saying, "Sure can!"

The project was assigned to (actually, grabbed with both hands by) Ralph Gutekunst, who worked together with me on my last project. After further emails and phone conversations we came up with a laundry list for the Ruger that would transform an already good revolver into a better one. Nothing outrageous, nothing extraneous-just some practical modifications to improve performance and handling beyond what the factory can do at the price levels set for the model. I think Ralph was actually more enthusiastic about the idea than I was, and that's always much better than hearing a custom gunsmith say, "You wanna do what??????!!!!!"

GP100 Makeover

First item on the list was that barrel lug. Gotta go, and go it went.

Next up was the sights. Ruger factory sights on the GP100s are adequate for many uses and most people, but they can be tremendously improved for us older geezers who can't find black-on-black on dark targets in a hurry anymore. Years ago, when I could still focus clearly on both front and rear handgun sights, I pretty much scorned the bright-colored front ramp inserts and white outline rear notches. Real men just didn't need that kind of foo-foo stuff. But...Time catches up with all of us eventually, and I've been duly caught up with. Nowadays I need either lots of light on both sides of the post in the notch, or something else to help my eye differentiate between the two. More and more, I'm finding that there was something to those inserts and outlines after all, and more and more, my handguns are beginning to reflect that where possible. We dis- cussed sights, and agreed that we were unlikely to find anything much better for the Ruger than Hamilton Bowen's Rough Country all-steel sights. The front sight on the GP is changeable, by depressing a plunger above the muzzle and removing it, and Bowen Ruger sights are drop-in replacements that don't require any alteration to the gun itself. Hamilton supplied a set for the GP, and Ralph installed a flat-faced gold bead in the front post that stands out well in most lighting and contrasts brightly with the white outlined rear notch. The sights are very rugged, fully adjustable, and provide a quick pickup at speed if necessary. Perfect for my eyes, and a marked improvement for an outdoors carry gun.

The factory triggers are fair, but tend to be a little on the heavy side. Ralph took the single-action pull from 4.25 down to 2.75 pounds, and the DA pull is plenty smooth. Absolute reliability with any and all primer brands was a must on a defensive handgun, and there wasn't a single problem even with the harder CCI primers in one of the factory test loads at the range. Too often, reliability suffers if you're not careful in lightening springs during action work-we're good here.

The last review was done with a blued GP to match the blued Security- Six, but for a keeper stainless steel seemed like a better all-weather way to go. Even the brushed stainless factory finish was brighter than I wanted, so a more subdued bead blasted finish was requested. There aren't many sharp edges on a GP100, but the rear corners of the trigger are sharp enough to shave with and the hammer spur can remove skin if you're not careful. Prior to the bead blasting, the gun got a carry bevel package that rounded those off, along with the cylinder latch thumbpiece. I prefer a smooth-faced rounded trigger on my DA revolvers - this one was rounded and polished brightly.

Other odds and ends included re- crowning the muzzle to an 11-degree "dish", chamfering the chambers for easier speed loader use, and a semi- Fitz triggerguard. Fitz what? In the first half of the 1900s, J. H. Fitz-Gerald was a showman, ballistics expert, gunsmith, and Colt rep famous for his Fitz Specials-revolvers with short barrels and triggerguards completely cut away from the trigger forward to the frame. The idea behind that triggerguard modification was to put the finger on the trigger right now, without the guard getting in the way to slow the process down. He frequently carried a matched pair of Fitz Special Colt New Service .45s in specially lined pants pockets, and Fitz Special Police Positives and Detective Specials in .38 caliber were popular for a while among dedicated pistoleros of the era. Today, a true Fitz Special would be labeled either Collector's Item or Lawsuit Pending. But, if you find yourself with gun in hand and finger off trigger, for whatever reason, the theory is that removing about half the width of the triggerguard on the left or right side just forward of the trigger (depending on a right-hand- ed or left-handed shooter) gives you marginally less obstructed access for a quick access to the trigger without running into the guard enroute. A semi- Fitz treatment may help fractionally while still maintaining the reason the guard was invented in the first place- protecting the trigger from being nudged and fired accidentally.

The final modification on the list was a very simple one even I could handle (literally) when the GP100 came back. Ruger equips the GP100s with two different versions of their Santoprene/walnut grips. The adjustable-sighted guns get the bigger grips, the fixed-sighted guns get slightly smaller and more rounded grips with a different profile and feel in the hand. After owning and shooting both over the years, I've come to prefer the overall fit of the smaller grips.

So, having worked all that out, I shipped a brand new stainless fourinch GP100 off to Cylinder & Slide, arranged for the sights with Hamilton Bowen, got a fixed-sight grip on the way from Ruger, and settled in for the hardest part...the wait. Finally, a call from C&S to say the Ruger was on its way home, and it was time to round up the gear and head for the gravel pit.

How It Shoots

Much of the .357's reputation as a hard-hitting medium bore magnum was built around a 158-grain bullet. Today we've got several very good factory rounds to choose from in other bullet weights. This particular GP was set up as an outdoors, or trail, gun but could easily pull duty as a concealed carry piece. It's not too heavy for daily CCW carry with lighter bullets, and it's not too light for the woods with heavier bullets.

I took six commercial loads to the pit along with two .38 Special loads for accuracy testing at 25 yards on my Outers Pistol Perch.

You can actually go even lower, but I don't see much use in anything below a 11 O-grain bullet in the caliber. If you want to shoot squirrels with a lighter bullet, you don't need a .357 Magnum handgun. The 110s and 125s were developed mostly for law enforcement use, and even though the 1 25s widely eclipsed them in popularity (and usually in performance) you still see a few people carrying the 110s for self- defense because of the lower recoil. The 158-grainer is the standard, and the 180-grainer makes a good penetrator with the right bullet type. All four weights were included to see how the GP100 would cover the field. There are also many people who buy a .357 Magnum revolver for its strength, but shoot more .38 Specials through it than anything else, and some .357 chambered guns shoot .38s better than others.

From the rest, the Ruger shot well enough for my purposes. Ralph tells me he can probably tweak it a little further, but the best five-shot groups are all I'll need in this trail gun.

The Ruger was very pleasant and easy at the bench. Recoil was stiffest with the Hornady and Speer loads, but the .357 Magnum, even in a relatively light revolver like this one, is not a major kicker. The .357's famous muzzle blast has been tamed somewhat with more modern powders, but it was still severe with the Gold Dots whose muzzle flash was visible in broad daylight. I've noted this before with the Gold Dot round -it's a good performer and I keep hoping Speer will incorporate a flash retardant powder one of these days, it'll blind you at night. Otherwise, the 110-grain Remington was very mild, the 180-grain Remington wasn't as hard on the hand as you'd think it would be, and the Winchester .38 Special 158-grain lead semi-wadcutter was a very consistent and low-recoil- ing load.

The point-of-impact varied by about six inches between the 1 25 and 180- grain bullets. Lighter loads lower, heavier loads higher, and that's why we have adjustable sights. You can swap back and forth between bullet weights in this gun without giving up much to accuracy, but just remember to set the sights to match your regular carry load if you ever have to use it for self- defense.

The GP was quite controllable under double-action rapid fire. It's not as light out front as the Security-Six. It still has a heavy barrel that helps with recoil, but it's better balanced than it was with the extra weight of the full barrel lug. After accuracy testing was done, I moved up to ten feet from the target stand and had no trouble getting a 4.75-inch six-shot group with the Blazers, and a 5-inch group with a mixed cylinder, on DA speed dumps.

Works for me.

Trail Gear

For trail carry, the GP100 rides perfectly in the same holster we used for the previous GP review, Bianchi's classic leather 5BHL high-ride thumb break. In these days of dwindling revolver holster choices, this remains one of the best production models at $89.50. One of the more comfortable and lightweight nylon belts to hang it on is Bianchi's Model 7225 ErgoTek for $62. Designed for police, you don't have to be one to use it, and the inside padding helps ease the load on a sunny spring hike. Speedloader pouches are likewise drying up, get yours while they're still available. The $31.25 synthetic 7901 AccuMold double pouch fits my favorite HKS speed loaders, and old habits from my early working days die hard, I still carry two double pouches.

The SOG SEAL Revolver, designed by Robbie Robertson, makes a fine lightweight trail partner for the GP. Like the Ruger revolver, the SOG Revolver is also stainless and corrosion resistant. One of the more sensibly innovative designs I've seen, it offers the genuine utility of two blades in one fixed-blade (sorta) knife. The Revolver's rotating blade locks into position with either a cutting blade out or a saw blade out. This is not a gimmick for the gullible, it's a serious knife, made of AUS-8 stainless with very aggressive saw teeth, and the company offers both well-designed leather and Kydex sheaths. The Revolver is also built with other blade types such as a tanto and hunting version with guthook main blade. At six ounces with lytel handle, it retails for $82.95.

For rough terrain, steep trails, crossing running water, and general hiking support, a good staff is well worth its weight, which, in the case of Stoney Point's PoleCat Outback I staff, is about 7 ounces. Made of hard-tempered aircraft aluminum alloy, the 48-inch Outback I is an outgrowth of the Stoney Point shooting stick line, and features an oversized closed cell foam handgrip and woven nylon wrist strap at the top. At the bottom, the rubber tip can be removed to use the carbide tip for better traction on rock and ice. It's a very handy bargain at $19.95, and we have three PoleCats here at home.

(Prices have changed, since the publication of this article, please visit our online store for the latest prices.) 

Final Notes

So, that's our Cylinder & Slide project for this year, one of the best trail guns going. As usual, the quality of the work is first rate. The better-balanced and rugged GP carries light with good support gear, the caliber is sufficient to solve many hostile outdoor problems (south of Alaska) with the right bullet choice, the sights are much improved, and the smooth rounded grips are extremely comfortable in a mid-sized hand. At 37 ounces, it's not quite a 35.5-ounce Security-Six, but it's not quite a normal 39.5-ounce GP100 either. The result is less weight than the current adjustable-sighted GP100, with better sights than the lighter 36-ounce fixed-sight GP. My thanks and appreciation to C&S, Hamilton Bowen, and Ruger for all their help.

The cost? $845 for the package (excluding the GP100), but as always, you can pick and choose which parts you'd like done to your own gun, and I'd heartily recommend at least the barrel work and Bowen sights, if you don't want to go the whole route right now. (Prices have changed, since the publication of this article, please visit our online store for the latest prices.)  For more pricing info check with C&S and Bowen Classic Arms.

The often under-appreciated Ruger GP100 is a solid performer, and you won't go wrong with these folks if you're interested in maximizing yours. .

For more information contact:

Cylinder & Slide, 245 E 4th St., Dept CH, Fremont, NE 68025; 800- 448-1713; www.cylinder-slide.com

Prices reflected in this article are respective to the date of the article.  Current prices will more than likely be different.