The Winchester Model 94 Big Bore Rifles
By Chuck Hawks
Winchester introduced their Model 94 Big Bore in 1978. It was built on a strengthened version of the regular Model 94 receiver intended to accommodate a new line of rimmed cartridges loaded to a maximum average pressure (MAP) of 52,000 CUP. (The internal parts were identical to the standard Model 94, only the receiver itself being beefed-up.) The new calibers were .307 Winchester, .356 Winchester and .375 Winchester. Serial numbers on Big Bore rifles were preceded by the letters "BB."
The Big Bore 94 was introduced while the Winchester Repeating Arms Company was still owned by Olin. It was, in fact, the last new model introduced by Winchester RAC. I understand that butt pads on the early rifles were marked, "Winchester Repeating Arms" if manufactured before January 1981. USRAC purchased the rights to the Winchester name in 1981 and rifles made under USRAC management were marked, "U.S. Repeating Arms Co."
The .307 Winchester and .356 Winchester were essentially rimmed, internally strengthened versions of the existing .308 and .358 Winchester cartridges, while the .375 Winchester was based on a slightly shortened and strengthened .38-55 case. Actually, although most owners do not realize it, .375 Big Bore 94 rifles can also shoot .38-55 cartridges, including the Buffalo Bore Heavy .38-55 +P load that exceeds the killing power of the Winchester .375 factory load.
I remember reading that, had the Big Bore 94 rifle and .375 Winchester cartridge been as commercially successful as hoped, the folks at Winchester intended to introduce a .45 caliber cartridge to complete the line. The anticipated sales never developed and the project was shelved.
From 1978 through 1983, Big Bore 94 rifles were built on the post-1964 top-eject action. The top eject action was supplied with standard Model 94 semi-buckhorn rear and hooded bead front sights and was drilled and tapped for receiver sights. In addition, side mounts for riflescopes were available.
When the Angle-Eject action became standard across the M-94 line, starting in 1982, the Big Bore rifles incorporated the new feature. Angle-Eject allows low and overbore scope mounting and AE receivers are drilled and tapped for top mounted scope bases. A folding rear sight replaced the earlier semi-buckhorn rear sight to clear a low mounted scope.
Big Bore 94 rifles received what Winchester called the XTR treatment, including a highly polished blued barreled action and a checkered walnut stock and fore end. The XTR designation was dropped in 1989, although the rifles remained the same.
The stock had a straight hand and terminated in a thin rubber butt pad. (Contrary to some reports, this was not a recoil pad.) Big Bore rifles circa 1983 had a Monte Carlo comb, others had a conventional straight comb. All Big Bore 94s were carbines with 20" round barrels and a full length, under barrel tubular magazine that held six cartridges.
In 1992, Winchester added an unsightly and generally disliked cross-bolt safety to the receiver of Model 94 rifles, including the Big Bore. This unnecessary safety (except to the Company lawyers) blocks the hammer when engaged. It stayed for the remaining years of Big Bore 94 production.
Big Bore 94 sales never met expectations and in 1997 the .375 cartridge was dropped from the Model 94 line, followed in 1998 by the .307 and .356 Winchester cartridges. Ammunition for all three calibers remains available from Winchester in 2018. Oddly, that same year (1998), the .444 Marlin was offered in the Big Bore 94.
The .307, .356 and .375 Winchester Cartridges
The .307 was introduced with a 150 grain bullet at a MV of 2760 fps and a 180 grain bullet at 2510 fps in Winchester factory loads. The .356 was offered with a 200 grain bullet at a MV of 2460 fps and a 250 grain bullet at 2160 fps, while the .375 came with a 200 grain bullet at 2200 fps and a 250 grain bullet at 1900 fps.
These were all Super-X loads using Power Point (flat point) bullets and the velocities were measured in 24" test barrels. (Expect around 40-80 fps lower MV from a 20" barrel.) The 180 grain .307, 200 grain .356 and 200 grain .375 loads proved to be the more popular offerings and they are the only factory loads that Winchester has offered in recent years.
The .307 and .356 were designed to provide ballistics similar to the .308 Win. and .358 Win. (The .307 Win. actually uses standard .308" diameter bullets and the .356 uses standard .358" bullets.) Except for their rims, the case bodies of the .307 and .356 are identical to, respectively, the .308 and .358. Reloaders can use .308 dies to reload .307 cases and .358 dies to reload .356 cases.
Due to the Model 94's tubular magazine, the new cartridges had to be loaded with flat point bullets. This meant that, while they started fast, they shed velocity rather quickly downrange. By 200 yards the ballistics of the .307 and .356 had fallen well behind the .308 and .358 Winchester cartridges with which they were usually compared.
For example, the current 180 grain Winchester Power Point flat point bullet used in the .307 Super-X factory load has a ballistic coefficient (BC) of .253, while the 180 grain Power Point spitzer bullet used in the Super-X .308 load has a BC of .382. The .307 Win. bullet starts at a muzzle velocity of 2510 fps, which is 110 fps slower than the .308. However, at 200 yards it is rolling along at 1874 fps, 302 fps slower than the .308 bullet. In fact, at 300 yards the 180 grain .308 bullet is still traveling about 100 fps faster than the .307 bullet does at 200 yards.
Likewise, the .356's 200 grain flat point bullet suffers in comparison to the .358 Winchester's 200 grain spitzer bullet, although less, as the starting velocities for both cartridges is lower. The 200 yard velocity difference is only about 80 fps in favor of the .358. Today, as loaded by Winchester, the .356 is the most powerful of the three Big Bore cartridges. The .356/200 grain load puts more energy on target at 100 yards (1985 ft. lbs.) than does the .307/180 grain (1795 ft. lbs.) or the .375/200 grain (1506 ft. lbs.).
The .375 Winchester is different in a couple of ways. For one thing, it is correctly named, as it actually uses .375" diameter bullets. Its high operating pressure (52,000 CUP) allowed it to easily outperform the earlier .38-55, which is held to only 30,000 CUP by SAAMI specifications and is loaded well below even this modest MAP by Winchester. (This comment does not include the Buffalo Bore Heavy .38-55 +P load, which is loaded to 38,000 CUP.)
The fact is, shooting high pressure loads using 250 grain bullets in a Model 94 carbine with a 20" barrel results in uncomfortable recoil. This is why, even though they were more potent, the 250 grain .356 and .375 factory loads were not popular with shooters and were eventually discontinued.
The sectional density (SD) of a .358", 200 grain bullet is .223, which in a powerful .35 caliber rifle is satisfactory for hunting all Class 2 and most Class 3 game. However, the SD of a .375", 200 grain bullet is only .203. This is fine for Class 2 animals, but marginal for the big Class 3 animals a .375 caliber rifle would seem best suited. In addition, the stubby bullet (BC .214) sheds velocity and energy quickly.
It is unfortunate that the Model 94 Big Bore was not offered as a rifle with a 24" barrel, rather than just a 6.5 pound carbine. Guns and Shooting Online has reviewed the new Winchester Model 94 Sporter .38-55 Rifle that weighs 7.5 pounds (bare) with a 24" barrel and about 8.5 pounds with a low power scope. This rifle comfortably handles the Buffalo Bore Heavy .38-55 +P load, which launches a 255 grain bulllet (SD .256) at a MV of 1950 fps, developing recoil similar to an eight pound .270 Winchester rifle. This is the type of rifle that would have made the .375/250 grain and .356/250 grain factory loads acceptable to more shooters. A properly designed .35-.37 caliber bullet weighing 250 grains at a MV of 1900-2100 fps is adequate for all North American big game.
According to the 36th Edition of Fjestad's Blue Book of Gun Values, Winchester 94 Big Bore rifles in all three calibers command a premium price, compared to standard Model 94 XTR rifles. They have, however, not yet been priced out of reach of shooters and hunters. A .307 in 100% condition is listed at $775 and in 98% condition at $600, while a .30-30 Model 94 XTR in 100% condition is listed at $650 and in 98% condition at $550. Add 25% for Big Bore 94s in .356 or .375 caliber.
In 2018, a new Winchester Model 94 Angle Eject Carbine carries a MSRP of $1199.99 in calibers .25-35, .30-30, .32 Win. Special and .38-55. Without question, the new Model 94's are beautifully made rifles. (See the Product Reviews page for full reviews of all the new M-94 Sporter rifles.) However, the price makes a nice Model 94 Big Bore Angle-Eject seem like a pretty good deal for the hunter who favors a powerful lever action carbine.
Copyright 2018 by Chuck Hawks. All rights reserved.