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Post by AxeHandle on Nov 24, 2019 19:13:09 GMT -5
We have 243 (6mm TCU), 257 (257 TCU), 264 (6.5 TCU), and 284 (7mm TCU) cartridges. Anyone else noticed the void at .277? First guess you might think the 270 REN scared them off but the REN was a 100 yard Hunter's Pistol Cartridge. Betting David Bradshaw has some information to share... How about it David?
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Post by Ken O'Neill on Nov 24, 2019 19:59:50 GMT -5
No, that's all of them. A .30 was also done by Tom Beall, but was never commercialized like the T/CU's. The 270 Ren. done by Jim Rock, was of course done on the .22 Hornet case.
The .300 Savage and .308 were wildcatted ad infinitum, the most famous of which were the 7mm International done on the Savage, and 7mm/308 later commercialized as the 7mm-08.
The number of wildcats used in the Metallic Silhouette game probably numbers in the hundreds.
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Post by bradshaw on Nov 24, 2019 21:07:41 GMT -5
No, that's all of them. A .30 was also done by Tom Beall, but was never commercialized like the T/CU's. The 270 Ren. done by Jim Rock, was of course done on the .22 Hornet case. The .300 Savage and .308 were wildcatted ad infinitum, the most famous of which were the7mm International and 7mm/308 later commercialized as the 7mm-08. ***** Axehandle.... there you have it. Wes Ugalde was a popular----on the firing line and in the winner’s circle----builder of IHMSA Ulimited pistols. All of the Ugalde (“U-gall-dee”) unlimiteds which I remember were built on the Remington XP-100 .221 Fireball. Ugalde rounds built on the .223 case rank as the easiest to form. The 6mm Ugalde, later called 6mm TCU, wrote the blueprint for 6mm’s in silhouette. These are low-stress, well behaved rounds. As well, they achieve accuracy over a substantial RPM range. Wes Ugalde said, “The XP-100 is a soft action,” at the same time recognizing its exceptional strength. Until Remington released the XP-100 7mm BR Remington in the winter of 1979-'80. (7mm BR designed by Jim Stekl of Remington and the Bench Rest Hall of Fame.) And, as Ken O’Neill notes, the .270 Ren was designed as a very tight shooting, flat trajectory round of minimal recoil for the Field Pistol/Hunter Pistol game. Minimal recoil allowed use of the .270 Ren with Short Eye Relief rifle scopes from a crunch offhand position called the Taco hold. Jim Rock of Rock Pistol Manufacturing (RPM, maker of the improved Merrill tip-open single shot), was the elder statesman of steel shooting. The initial surge of .30’s in IHMSA was championed in XP-100 .308x1-1/2" by Jose Porras of Mexico, Tom Beall on .223 brass in the T/C Contender, I think, various Contenders in .30 Herrett and .30-30 Win., along with XP’s and Wichitas in .308 Win. Of the .30’s, the old factory rounds .30-30 and .308 Winchester outlasted the wildcats. Watching steel shooters turn the Contender into an auto-ejector inspired Warren Center to beef up his versatile single shot. David Bradshaw |
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Post by bigbrowndog on Nov 24, 2019 21:28:40 GMT -5
Lack of good target bullets may be the reason for no 270.
Trapr
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Post by Encore64 on Nov 24, 2019 21:32:17 GMT -5
Plus there was the 270 Verne Juenke and 270 Ingram...
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Post by bradshaw on Nov 25, 2019 8:04:51 GMT -5
Jacketed hunting bullets constituted the vast majority of projectiles fired through single shots by steel shooters. Most match bullets are of boattail persuasion, offering no advantage in IHMSA silhouette. In fact, a boattail is more bore-sensitive that a flat base. And, more twist-sensitive at handgun velocities. The 7mm rose in popularity as ballistics combined downrange performance with reduced recoil. The 7mm became the alternative to the .30 for effectiveness against the 55-pound ram, set full-foot @ 200 meters. Once a rule was adopted----the “topple rule,” allowing rams’ feet to overhang the rail----smaller bores began to have a chance. Allowing the 6mm to stick its toe in the door. The .277 had always been a hunting diameter, despite accuracy never considered a target bullet, which may have blocked it from popular consideration.
Good hunting bullets record extreme accuracy from single shot pistols. Prior to departing for one championship, my last three shots were fired at a chicken painted on cardboard and stapled up @ 200 meters. The pistol: factory Remington XP-100 7mm BR rechamsbered to 7mm IHMSA with the straighter chamber required to clean up the “BR shoulder,” which otherwise would show up on the body of a fired case; Redfield International Globe with .075-inch post and Bo-Mar rear sight; set in the fine H-S Precision fiberthane center-grip stock, with aluminum bedding block. The ammo: Hornady 175 grain Spire Point seated over 30.8/IMR or Hodgdon 4895 in 7mm IHMSA (Federal) brass, (I’d have to look up primer), for 1,800 or 2,000 fps. I’d have to check on data, as velocity difference has to do with leade length. I had the leade cut short enough to jam bullet, and to allow for erosion growth, but mostly for efficiency of powder/velocity. Ammo loaded in Redding dies cut for the straighter re-chamber. (This is why there are two 7mm IHMSA chambers: one for a new barrel; the other for a re-chamber of the 7mm BR Rem. Both have 38-degree shoulder. Dies should match.
Creedmoor position.... iron sights, 3x3 shots = 5/8-inch @ 200 meters. That Hornady 7mm 175 Spire Point is a hunting bullet, and it will push a ram. This combo later won the infamous shootoff at the Florida Sun Shoot.
T/C Contender barrels varied in accuracy, a detail noticed by steel shooters which gave rise to a lot of re-barreling for Unlimited guns.
David Bradshaw
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Post by squigz on Nov 25, 2019 8:23:35 GMT -5
I love the TCU calibers and I've always wondered the same about the .277 one. Makes sense why it never made waves since there was already everything out there to do what it would do and better with the 7mmTCU.
I'd like to add one of each of the TCU barrels for my contender, more specifically a 25TCU. My 7mmTCU is a beautiful shooter as it stands now and I would hesitate to pick up a 6 or a 6.5 if one came up locally.
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Post by magman on Nov 25, 2019 8:27:06 GMT -5
Have the 6 and 6.5 tcu. Would love to find a 257tcu someday.
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Post by potatojudge on Nov 25, 2019 12:16:45 GMT -5
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Post by AxeHandle on Nov 25, 2019 17:05:29 GMT -5
I have a 6mm TCU Virgin Valley TC barrel. Best I read Virgin Valley became MGM.. Just traded for a MGM 257 TCU barrel.
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Post by junebug on Dec 13, 2019 18:38:01 GMT -5
I just picked up a 14 in. 6.5 tcu for my son today, he's out bear hunting. I have a 10 in 7 tcu that shoots very well. It will be interesting to compare them side by side.
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Post by bradshaw on Dec 13, 2019 19:59:24 GMT -5
I just picked up a 14 in. 6.5 tcu for my son today, he's out bear hunting. I have a 10 in 7 tcu that shoots very well. It will be interesting to compare them side by side. ***** Hodgdon 4895 and Dupont IMR 4895 represent to this shooter the all-time all-around MEDIUM BURN RATE RIFLE POWDER. Emphatically this includes Wes Ugalde’s cartridges built on the .223 Rem case. Along with wildcats on the .300 Savage case (7mm IHMSA, etc.), and the .308 Win case. No other powder comes close to the 4895 I’ve burned in bottleneck silhouette brass. First powder I tried in the then soon to be released 7mm TCU was IMR 4198, entirely match accurate. Wouldn’t hesitate to load the 6.5mm TCU with IMR 4198. These cases shoot a variety of medium powders well with a span of bullets weights. H4895 and IMR 4895 are the hub of the wheel. I have interchanged IMR & Hodgdon 4895 in silhouette rounds built on .223, .300 Savage, and .308 Win brass without accuracy loss or shift in sight settings in competition. Powder charges always thrown from one of these measures: Redding BR, RCBS Uniflow, or Neil Jones Custom Products Micro Measure. Scale used only to adjust charge; all charges thrown from measure. David Bradshaw |
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Post by AxeHandle on Dec 14, 2019 6:45:57 GMT -5
The brass used to form the family of TCU cases deserves a little discussion. I've recently been pointed toward Winchester 223 brass.
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Post by bradshaw on Dec 14, 2019 11:27:06 GMT -5
The brass used to form the family of TCU cases deserves a little discussion. I've recently been pointed toward Winchester 223 brass. ***** Can’t speak for brass cranked out now. In 1979----and thereafter----my 7mm TCU brass began as fresh Federal .223 Rem: * Brush inside neck of .223 case with mix of graphite and Brownell’s Dry Slide, molydisulfide in evaporative medium. * Pass case over a PROGRESSIVE EXPANDER to 7mm. * Chamfer very lightly. (Trim only if necessary; usually not necessary.) * Prime with small rifle primer. A usual load of 139, 140, 150, or 160 grain 7mm spitzer over 24/H4895. Bullets are seated long. Because of the Contender freeborn, you cannot seat to engrave rifling, which in any event you wouldn’t do, as the tip-open action lacks the calming power of a bolt an misfires would result. The case fireforms a 40-degree shoulder. The fireforming shot is match accurate, a beauty of TCU cartridges absent rifles. Many early silhouettes took advantage of plentiful surplus/range pickup 5.56 and 7.62 brass. I didn’t mess with military M-16 brass, but enjoyed great success with matched-lot 7.62x51mm brass from Twin Cities Arsenal. Other Americam 7.62 brass also fine. (Note, I did not try to form short BR Rem brass from surplus.) I neck iced the fireformed case whener possible, which may be only once before the Full Length sizer is necessary for proper engagement of Contender locking lugs. I would expect Winchester .223 to be fine for Contenders. All sorts of aggravation is avoided by staying below firewall loads in the tip-open Contender. David Bradshaw |
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