ALLEN MAGNUM, ALLEN XPRESS AND ALLEN TACTICAL WILDCATS
2007
Listed below are the current members of the Allen Precision family of wildcat chamberings. Included you will find the name of the wildcat chambering, parent case used for the wildcat, preferred bullet for each specific wildcat chambering and average performance from listed barrel lengths. Also listed is intended use and appropriate loading powders for each.
Allen Magnum Wildcats
.224 Allen Magnum 270 WSM parent case, fireformed to sharper shoulder angle and less body taper 80 gr. up to 100 gr. Ultra Low Drag(ULD) Rebated Boattail(RBBT), still in development at this time 3450 to 3550 fps in 27" barrel Designed for long range coyote hunting with minimum pelt damage. Also intended for pronghorn hunting and lighter deer at moderate ranges(400 yards and less. Appropriate loading powders: H-870, H-US869, AA8700 and WC872
257 Allen Magnum 338 Rem Ultra Magnum parent case, necked down to 257, fireformed to min body taper and sharper shoulder angle. 100 gr.(4100 fps)up to 156 gr. ULD RBBT(.820 bc) 3350 fps in 30" barrel length Design purpose for long range pronghorn and deer hunting. Out to 800 yards on heavy deer, 1000+ on pronghorns. Also makes a very effective long to extreme range coyote rifle but a bit hard on pelts Appropriate powders: H-870, H-US869, AA8700 and WC872
6.5mm Allen Magnum 338 Rem Ultra Magnum parent case, necked down to 6.5mm, fireformed to min body taper and sharper shoulder angle. 168 gr ULD RBBT (still in development) 142 gr. SMK or ULD RBBT at 3450 fps with 142 gr. in 27" barrel, 3550 fps in 30" barrel lengths. Same design purpose as 257 Allen Magnum but designed for those that prefer the larger selection of 6.5mm bullets. Appropriate powders: same as 257 Allen Magnum
270 Allen Magnum 300 Rem Ultra Magnum parent case, necked to 270 and fireformed to min body taper and sharper shoulder angle. 130 gr.(3800 fps) up to 169.5 gr ULD RBBT(.740 bc) 3300 fps in 27" barrel length, 3400 fps in 30" barrel length Designed for game up to 500 lbs at long range, deer and pronghorn out to any range a shooter can place the bullet in the vital zone of his target. Appropriate powders: H-870, H-US869, AA8700 and WC872
277 Allen Magnum 338 Lapua Magnum parent case, necked down to 270 and fireformed to min body taper and shoulder angle. 140 gr.(3750 fps) up to 195 gr ULD RBBT(.920 bc) 3250 to 3300 fps from 28 to 30" barrel lengths Designed for long range precision big game hunting. Usible on game up to and including elk and moose even out to 1000 yards. Appropriate powders: H-US869, H-870, AA8700 and WC872
7mm Allen Magnum 338 Lapua Magnum parent case, necked down to 7mm and fireformed to min body taper and shoulder angle. 140 gr.(3800 fps) up to 200 gr. ULD RBBT(.900 bc) 3200 to 3350 fps from 26" to 30" barrel lengths Designed for long range big game hunting up to and including elk and moose. Has been used effectively on elk out to 1300 yards and has also proven one of the most ballsitically potent rounds in use today including the 277 Allen Magnum and the 338 Allen Magnum. Has proven capable of ½ moa accurate out to 1000 yards and 1 moa accurate out to 2800 yards in good conditions. Appropriate powders: H-Retumbo, H-50BMG, H-870, H-US869, AA8700 and WC872
338 Allen Magnum 408 Cheyenne Tactical parent case, necked down to 338, shoulder moved roughly 50 thou forward and fireformed to min body taper and sharper shoulder angle. 265 gr. AT RBBT(.920 bc) at 3500 fps in 32" barrel up to 350 gr. ULD RBBT at 3200 fps in 32" barrel. Designed for heavy big game hunting at long range or standard big game hunting out to extreme range. Has been proven consistant and accurate out to 3008 yards by holding moa accurate out to this range and remaining super sonic in velocity with the 265 gr. AT RBBT. Appropriate powders: H-50BMG(recommended), H-870, AA8700, US869, WC872, VV 20N29
375 Allen Magnum 408 Cheyenne Tactical parent case, necked down to 375, shoulder moved forward 50 thou and fireformed to min body taper and sharper shoulder angle. 300 gr.(3400 fps in 32" barrel, est.) to 350 gr. SMK at 3300 fps in 32" barrel(est.) Designed for heavy game hunting or any application where extreme ballistic performance is wanted with a very large kenetic energy payload on impact. Appropriate powders: H-Retumbo, RL-25, H-50BMG (est.) still in research and development stages at this point.
510 Allen Magnum 50 BMG parent case, fireformed to min body taper and sharper shoulder angle. 750 gr. A-Max or ULD RBBT at 2900 fps in 34" barrel length Designed for heavy game hunting where legal and extreme range target shooting. Appropriate powders: H-50BMG, WC872, H-US869, VV 20N29
Allen Xpress Wildcats
257 Allen Xpress 300 Dakota parent case, necked to 257 and fireformed to the Allen Magnum shoulder and body configuration. 100 gr. (3750 fps in 28" barrel) to 156 gr. ULD RBBT at 3050 fps in 27" barrel and 3125 fps in 30" barrel lengths. Designed for conventional deer hunting out to 600-700 yards. Appropriate powders: Ramshot Magnum, H-US869, H-870, AA8700 , WC872
6.5mm Allen Xpress 300 Dakota parent case, necked to 6.5mm and fireformed to Allen Magnum shoulder and body configuration. 100 gr. (3800 fps in 30" barrel) to 168 gr. ULD RBBT (still under development) Designed for same use as 257 Allen Xpress but for those that prefer the 6.5mm bore diameter. Appropriate powders: same as those for 257 Allen Xpress
270 Allen Xpress 300 Dakota parent case, necked to 270 and fireformed to Allen Magnum shoulder and body configuration. 130 gr. (3500 fps in 30") to 169.5 gr. ULD RBBT at 3200 fps in 30" barrel Designed for medium size big game out to ½ mile range. Appropriate powders: H-1000, Rl-25, Retumbo, Ramshot Magnum
300 Allen Xpress 338 Lapua Magnum parent case, necked to 30 cal and fireformed to the Allen Magnum shoulder and body configuration. 180 gr. (3450 to 3550 fps in 27-30" barrel) to 265 gr. ULD RBBT(3000-3100 fps in 27-30" barrel) Designed for medium to heavy game at long range, deer, elk and moose specifically Appropriate powders: H-1000, Retumbo, Rl-25, US869
338 Allen Xpress 338 Lapua Magnum parent case, fireformed to Allen Magnum shoulder and body configuration. 200 gr. (3350 to 3450 fps in 27-30" barrels) to 300 gr. SMK or ULD RBBT (2850 to 2950 fps in 27-30" barrels) Designed for heavy game out to long range. Appropriate powders: H4831, Rl-22, Rl-25, H-1000, Ramshot Magnum, Retumbo
375 Allen Xpress 338 Lapua Magnum parent case, necked up to 375 and fireformed to Allen Magnum shoulder and body configuration. 260 gr. (3150 to 3250 fps in 27-30" barrels) 300 gr. (2900 to 3000 fps in 27-30" barrels) Designed for heavy and dangerous game. Appropriate powders: H-4350, H-4831, Rl-19, Rl-22
Allen Tactical Wildcats
458 Allen Tactical 408 Cheyenne Tactical parent case, Necked to 458 and fireformed to Allen Magnum shoulder and body configuration. Bullets under development: 600 to 750 gr. ULD RBBT, estimated velocity 2550 to 2350 fps in 32" barrel. Designed for heavy tactical use or Dangerous game hunting. Appropriate powders: Still under research and development stanges 50 Allen Tactical 408 Cheyenne Tactical parent case, Necked up to 510 cal and fireformed to Allen Magnum shoulder and body configuration. 750 gr. ULD RBBT or A-Max(2450 fps in 32" barrel) Designed for heavy tactical use for 50 BMG class performance but in much smaller and lighter tactical style rifles. Also usable for dangerous game hunting.
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