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Posted: 6/23/2013 6:50:36 PM EDT
| I have an 11.5 AA piston rifle and reloading for the gun... no matter what I do I cannot seem to get 3k fps out of my loads with 55 53 or 60 gr bullets.... using blc2 or h322 any suggestions or data ? |
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If it has an 11.5" barrel.... well, there's your problem. I kinda though that would be the issue but ... surly their is a way to bump up the fps a little more then 2800 I don't see how you can safely move a 55 grain projectile in 5.56 out of an 11.5 inch barrel 
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If it has an 11.5" barrel.... well, there's your problem. I kinda though that would be the issue but ... surly their is a way to bump up the fps a little more then 2800 I don't see how you can safely move a 55 grain projectile in 5.56 out of an 11.5 inch barrel hmm not sure what your getting at ? I shoot LC out of mine at its pretty accurate inside 100 never shot it past that to see what its accurace is |
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If it has an 11.5" barrel.... well, there's your problem. I kinda though that would be the issue but ... surly their is a way to bump up the fps a little more then 2800 I don't see how you can safely move a 55 grain projectile in 5.56 out of an 11.5 inch barrel hmm not sure what your getting at ? I shoot LC out of mine at its pretty accurate inside 100 never shot it past that to see what its accurace is 2800 FPS is pushing it out of an 11.5 barrel. <2700 is far more realistic. |
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I am using the rifle for HD, and from what I gather the hornady v-max and most other 223 bullets are designed to "work" best at 3k + fps.... not sure if this is true or not as I am pretty much new to reloading for 223
I am loading 62 grain and 53 grain and also some 55 grain fmj, because of what I have read this is why I am trying to reach 3k fps or so... also I think a guy from barns told me the tsx bullet I think is also set to perform best at those fps if any one can set me straight please do.,... I do know with 27.5 grain of blc2 and 23.5 of h322 I am getting awesome accuracy that's for sure.... but I am not sure if at 2755 fps (average) I am getting the best terminal performance ( I could buy the gel but ) |
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I am using the rifle for HD, and from what I gather the hornady v-max and most other 223 bullets are designed to "work" best at 3k + fps.... not sure if this is true or not as I am pretty much new to reloading for 223 I am loading 62 grain and 53 grain and also some 55 grain fmj, because of what I have read this is why I am trying to reach 3k fps or so... also I think a guy from barns told me the tsx bullet I think is also set to perform best at those fps if any one can set me straight please do.,... I do know with 27.5 grain of blc2 and 23.5 of h322 I am getting awesome accuracy that's for sure.... but I am not sure if at 2755 fps (average) I am getting the best terminal performance ( I could buy the gel but ) There's a reason why SBR's are specialty weapons... Short barrels trade compact size and easy of handling for terminal performance at range and velocity. I think you've just figured it out. If you want velocity, get a longer barrel or lighter bullets. Otherwise, find ammunition that performs well at slower velocity. I'm not a big SBR guy, but if memory serves I think the TSX is one of the best. I'm sure the SBR crowd will chime in with their favorites. |
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I am using the rifle for HD, and from what I gather the hornady v-max and most other 223 bullets are designed to "work" best at 3k + fps.... not sure if this is true or not as I am pretty much new to reloading for 223 I am loading 62 grain and 53 grain and also some 55 grain fmj, because of what I have read this is why I am trying to reach 3k fps or so... also I think a guy from barns told me the tsx bullet I think is also set to perform best at those fps if any one can set me straight please do.,... I do know with 27.5 grain of blc2 and 23.5 of h322 I am getting awesome accuracy that's for sure.... but I am not sure if at 2755 fps (average) I am getting the best terminal performance ( I could buy the gel but ) Again, you are not going to get 2800 FPS let alone 3000 FPS out of an 11.5 inch barrel in 5.56 safely. |
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Barrel_____ (55gr M193)_____(62gr SS109)
Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 |
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Try a 50 grain bullet and H322. I had a 14" T/C in .223 that would run 3k FPS. Hornady's 50gn Z-max or Barnes 50gn Varmint Grenade, would be very effective for home defense. Also less worry about going through walls. Your pushing pressure, with the above bullets you could back it down to 2800fps and have great results. |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Even those velocities are a little unrealistic, just over 3K fps from a 16" barrel is pushing it and most factory ammo like Hornady 55gr Z-Max only produce 2930 fps from a 16" barrel. --- I load the 55gr V-Max with 25gr's of Benchmark at 3020 fps and thats a pretty stout load, not many powders will beat that staying within safe operating pressure. Here is the QL estimate that matches my load data and the new Nosler data very closely, 3020 fps from a 16" barrel, 3303 fps from a 24" barrel and 2760 fps from a 11.5" barrel. Cartridge : 5.56 mm NATO - 5.56 x 45 mm Bullet : .224, 55, Hornady V-MAX FB 22271-72 Useable Case Capaci: 25.849 grain H2O = 1.678 cm³ Cartridge O.A.L. L6: 2.260 inch = 57.40 mm Barrel Length : 16.0 inch = 406.4 mm Powder : Hodgdon Benchmark Predicted data by increasing and decreasing the given charge, incremented in steps of 2.0% of nominal charge. CAUTION: Figures exceed maximum and minimum recommended loads ! Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time % % Grains fps ft.lbs psi psi % ms -20.0 85 20.00 2407 707 31961 8146 82.7 0.997 -18.0 87 20.50 2467 743 34106 8429 84.1 0.969 -16.0 90 21.00 2528 780 36396 8708 85.5 0.943 -14.0 92 21.50 2589 819 38840 8982 86.8 0.914 -12.0 94 22.00 2650 858 41449 9250 88.1 0.886 -10.0 96 22.50 2712 898 44237 9512 89.3 0.859 -08.0 98 23.00 2773 939 47217 9767 90.5 0.834 -06.0 100 23.50 2835 982 50405 10013 91.6 0.809 -04.0 102 24.00 2897 1025 53816 10250 92.6 0.785 ! Near Maximum ! -02.0 104 24.50 2959 1069 57470 10477 93.6 0.761 ! Near Maximum ! +00.0 107 25.00 3021 1115 61388 10692 94.6 0.739 ! Near Maximum ! Cartridge : 5.56 mm NATO - 5.56 x 45 mm Bullet : .224, 55, Hornady V-MAX FB 22271-72 Useable Case Capaci: 25.849 grain H2O = 1.678 cm³ Cartridge O.A.L. L6: 2.260 inch = 57.40 mm Barrel Length : 11.5 inch = 292.1 mm Powder : Hodgdon Benchmark Predicted data by increasing and decreasing the given charge, incremented in steps of 2.0% of nominal charge. CAUTION: Figures exceed maximum and minimum recommended loads ! Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time % % Grains fps ft.lbs psi psi % ms -20.0 85 20.00 2164 572 31961 11165 77.3 0.834 -18.0 87 20.50 2221 602 34106 11602 78.8 0.810 -16.0 90 21.00 2279 634 36396 12037 80.3 0.787 -14.0 92 21.50 2337 667 38840 12471 81.8 0.762 -12.0 94 22.00 2396 701 41449 12902 83.2 0.738 -10.0 96 22.50 2456 737 44237 13328 84.6 0.715 -08.0 98 23.00 2516 773 47217 13749 86.0 0.692 -06.0 100 23.50 2576 810 50405 14163 87.3 0.670 -04.0 102 24.00 2637 849 53816 14568 88.5 0.649 ! Near Maximum ! -02.0 104 24.50 2698 889 57470 14963 89.8 0.629 ! Near Maximum ! +00.0 107 25.00 2760 930 61388 15346 90.9 0.610 ! Near Maximum ! Cartridge : 5.56 mm NATO - 5.56 x 45 mm Bullet : .224, 55, Hornady V-MAX FB 22271-72 Useable Case Capaci: 25.849 grain H2O = 1.678 cm³ Cartridge O.A.L. L6: 2.260 inch = 57.40 mm Barrel Length : 24.0 inch = 609.6 mm Powder : Hodgdon Benchmark Predicted data by increasing and decreasing the given charge, incremented in steps of 2.0% of nominal charge. CAUTION: Figures exceed maximum and minimum recommended loads ! Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time % % Grains fps ft.lbs psi psi % ms -20.0 85 20.00 2677 875 31961 5393 87.9 1.259 -18.0 87 20.50 2740 917 34106 5554 89.1 1.225 -16.0 90 21.00 2803 960 36396 5711 90.3 1.192 -14.0 92 21.50 2866 1003 38840 5862 91.4 1.157 -12.0 94 22.00 2929 1048 41449 6008 92.5 1.124 -10.0 96 22.50 2992 1093 44237 6148 93.5 1.092 -08.0 98 23.00 3054 1139 47217 6281 94.4 1.062 -06.0 100 23.50 3117 1186 50405 6406 95.3 1.032 -04.0 102 24.00 3179 1234 53816 6524 96.1 1.003 ! Near Maximum ! -02.0 104 24.50 3241 1283 57470 6634 96.8 0.976 ! Near Maximum ! +00.0 107 25.00 3303 1332 61388 6735 97.4 0.949 ! Near Maximum ! |
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If it has an 11.5" barrel.... well, there's your problem. I kinda though that would be the issue but ... surly their is a way to bump up the fps a little more then 2800 I don't see how you can safely move a 55 grain projectile in 5.56 out of an 11.5 inch barrel You mean at that sort of speed? 55gr in a short barrel is still fine. I'm curious as to why you think otherwise. |
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thanks for all the good info... so far according to my chrony and 10 shot strings I am getting on average 2780 fps, I have collected all my bras and don't seen any signs of over pressure, but I am loading
near maximum using the data out of my hornady magazine so I think I am going to not push my luck and stick to the suggested data in the book. I also hope the v-max work well at that velocity, I might try some lighter loads or maybe I will give up velocity and stick with some heavier bullets such as 60 or 62 grain bullets |
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Hey EWP, got a little tip for you when posting Quickload data.
Copy your data to "clipboard". Then when post on the forum type this and paste your data between the brackets. 
Your QL data will appear like this. Cartridge : 5.56 mm NATO - 5.56 x 45 mm |
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Unless you have more barrel for the propellent to burn in, you can not safely get 3K fps from your 11.5 inch barrel. Terminal bullet performance does typically depend upon velocity, and your velocity depends on the barrel length.
A longer barrel gives your bullet a greater performance window because it starts out of the rifle at a higher speed.... so it is still travelling faster at a farther distance. While your 11.5 barrel starts it out slower , thereby limiting its performance window. In other words if the bullet works best at 2600fps- 3300fps.... starting it out of your barrel at 2700fps is going to limit its effective range. And 3300fps is going to give it much more range. Bottom line .... you need more barrel for more speed. I truly think you reasonably understand the performance aspect , just not the " you need more barrel length part " Less barrel length gives the propellent less space to be burnt effectively.... another excellent example is the .357 Magnum and .44 Rem. Magnum. Compare the info in the link. Look at the linked page... it is explained quite well. And no offense intended but you need to read the section from your reloading manual on ballistics. http://www.ballisticsbytheinch.com/223rifle.html http://www.ballisticsbytheinch.com/scope.html |
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Unless you have more barrel for the propellent to burn in, you can not safely get 3K fps from your 11.5 inch barrel.
Barrel length has little or nothing to do with propellant burn as all the powder that is going to burn is burned up in the chamber and the first few inches of the barrel. It does not continue to burn all the way down the bore. The powder that give the highest velocity in a long barrel will also give the highest velocity in a short barrel. |
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Hey EWP, got a little tip for you when posting Quickload data. Copy your data to "clipboard". Then when post on the forum type this and paste your data between the brackets. http://i2.photobucket.com/albums/y17/steve4102/code_zpsa504e3e8.jpg Your QL data will appear like this. <snip> Thanks!!! |
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Hey EWP, got a little tip for you when posting Quickload data. Copy your data to "clipboard". Then when post on the forum type this and paste your data between the brackets. http://i2.photobucket.com/albums/y17/steve4102/code_zpsa504e3e8.jpg Your QL data will appear like this. Cartridge : 5.56 mm NATO - 5.56 x 45 mmBullet : .224, 55, Hornady V-MAX FB 22271Cartridge O.A.L. L6: 2.260 inch or 57.40 mmBarrel Length : 16.0 inch or 406.4 mmPowder : Hodgdon BenchmarkPredicted data by increasing and decreasing the given charge,incremented in steps of 2.0% of nominal charge.CAUTION: Figures exceed maximum and minimum recommended loads !Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time % % Grains fps ft.lbs psi psi % ms-20.0 85 20.00 2405 706 31875 8144 82.7 0.999-18.0 87 20.50 2465 742 34011 8427 84.1 0.971-16.0 89 21.00 2526 779 36290 8706 85.5 0.944-14.0 91 21.50 2587 817 38723 8980 86.8 0.915-12.0 94 22.00 2648 856 41321 9249 88.1 0.887-10.0 96 22.50 2709 896 44096 9511 89.3 0.861-08.0 98 23.00 2771 938 47061 9766 90.4 0.835-06.0 100 23.50 2833 980 50232 10013 91.6 0.810-04.0 102 24.00 2894 1023 53625 10250 92.6 0.786 ! Near Maximum !-02.0 104 24.50 2956 1067 57260 10477 93.6 0.763 ! Near Maximum !+00.0 106 25.00 3019 1113 61156 10693 94.5 0.740 ! Near Maximum !+02.0 108 25.50 3081 1159 65337 10897 95.4 0.719 !DANGEROUS LOAD-DO NOT USE!+04.0 111 26.00 3143 1206 69830 11088 96.2 0.698 !DANGEROUS LOAD-DO NOT USE!+06.0 113 26.50 3205 1255 74664 11265 96.9 0.678 !DANGEROUS LOAD-DO NOT USE!+08.0 115 27.00 3268 1304 79873 11427 97.6 0.658 !DANGEROUS LOAD-DO NOT USE!+10.0 117 27.50 3330 1354 85495 11573 98.2 0.639 !DANGEROUS LOAD-DO NOT USE!Results caused by ± 10% powder lot-to-lot burning rate variation using nominal chargeData for burning rate increased by 10% relative to nominal value:+Ba 106 25.00 3168 1226 71690 10880 98.7 0.689 !DANGEROUS LOAD-DO NOT USE!Data for burning rate decreased by 10% relative to nominal value:-Ba 106 25.00 2831 979 50927 10095 87.3 0.806 Thanks allot, I always wondered how to do that. EWP |
You can do it with other "copy" data as well. like Hodgdons web page.
55 GR. SPR SP Hodgdon CFE 223 .224" 2.200" 26.0 3133 43,300 PSI 27.8 3329 51,300 PSI |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Every barrel is a little different, but in my 11.5 I get 2879 average suppressed and 2918 unsuppressed with M193 and M855 is 2730/2736 for the same, so that's a fair representation. I wouldn't load any hotter than that. What's so special about 3K, anyway? It's just a number. |
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You seem stubornly stuck on that pistol-length barrel & 3,000 FPS.
The AR-15 RIFLE was designed around a 20" barrel. I suggest that. The M4 civilian CARBINE uses a barrel just over 16." That might get you closer to your somewhat arbitrary goals. Or, if you are STILL stuck on that little barrel, you should buy some 30 to 35 grain bullets and work up a load exceeding 3,000 FPS. You simply cannot expect rifle performance from what is essentially a pistol barrel. |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Every barrel is a little different, but in my 11.5 I get 2879 average suppressed and 2918 unsuppressed with M193 and M855 is 2730/2736 for the same, so that's a fair representation. I wouldn't load any hotter than that. well as long as I am in the normal ball park for this barrel length I can live with that..... What's so special about 3K, anyway? It's just a number. |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Source? |
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If it has an 11.5" barrel.... well, there's your problem. I kinda though that would be the issue but ... surly their is a way to bump up the fps a little more then 2800 I don't see how you can safely move a 55 grain projectile in 5.56 out of an 11.5 inch barrel You mean at that sort of speed? 55gr in a short barrel is still fine. I'm curious as to why you think otherwise. I meant at 3k FPS, of course 55 grain projectiles are safe out of an 11.5 inch barrel. |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Source? "Test shots were from a Bushmaster XM15E2 AR-15 type rifle, except for 21.5" value, which was from a Bushmaster M17S bullpup rifle.. Velocities found from average of three rifles each firing 5 shot groups, for a total of 15 shots for each value. Test conditions were: 0 degrees Fahrenheit. Barrel rifling - right hand twist, 20% of bullet length." FROM: How Barrel Length Affects 5.56x45 Muzzle Velocity |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Source? I checked out his site, not really sure who that person is. Perhaps they were able to work a load to >2800 FPS, be curious to see how loads looked at higher temps. However it is still not the 3k number, nor is there any bullet powder combo from an 11.5" barrel that will give you 3k FPS that is safe. "Test shots were from a Bushmaster XM15E2 AR-15 type rifle, except for 21.5" value, which was from a Bushmaster M17S bullpup rifle.. Velocities found from average of three rifles each firing 5 shot groups, for a total of 15 shots for each value. Test conditions were: 0 degrees Fahrenheit. Barrel rifling - right hand twist, 20% of bullet length." FROM: How Barrel Length Affects 5.56x45 Muzzle Velocity |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Source? "Test shots were from a Bushmaster XM15E2 AR-15 type rifle, except for 21.5" value, which was from a Bushmaster M17S bullpup rifle.. Velocities found from average of three rifles each firing 5 shot groups, for a total of 15 shots for each value. Test conditions were: 0 degrees Fahrenheit. Barrel rifling - right hand twist, 20% of bullet length." FROM: How Barrel Length Affects 5.56x45 Muzzle Velocity I checked out his site, not really sure who that person is. Perhaps they were able to work a load to >2800 FPS, be curious to see how loads looked at higher temps. However it is still not the 3k number, nor is there any bullet powder combo from an 11.5" barrel that will give you 3k FPS that is safe. |
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Here is another test with various barrel lengths in 223.
http://www.accuratereloading.com/223sb.html |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Every barrel is a little different, but in my 11.5 I get 2879 average suppressed and 2918 unsuppressed with M193 and M855 is 2730/2736 for the same, so that's a fair representation. I wouldn't load any hotter than that. well as long as I am in the normal ball park for this barrel length I can live with that..... What's so special about 3K, anyway? It's just a number. Just understand that by trying to duplicate M193/M855 loads, you're loading on the very hot end of things. For my mileage, I load 55 grain bullets to around 2800 fps out of a 16" barrel, and 62's to about 2750. I could probably push it a good bit further, but I really don't see a point to doing so. |
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Barrel_____ (55gr M193)_____(62gr SS109) Length______Velocity_______ Velocity 10"_________2739__________2627 11.5"________2872__________2738 14.5"________3064__________2907 16"_________3132___________2989 20"_________3259___________3095 21.5"________3386___________3185 24"_________3315____________3158 26"_________3391____________3231 Every barrel is a little different, but in my 11.5 I get 2879 average suppressed and 2918 unsuppressed with M193 and M855 is 2730/2736 for the same, so that's a fair representation. I wouldn't load any hotter than that. well as long as I am in the normal ball park for this barrel length I can live with that..... What's so special about 3K, anyway? It's just a number. Just understand that by trying to duplicate M193/M855 loads, you're loading on the very hot end of things. For my mileage, I load 55 grain bullets to around 2800 fps out of a 16" barrel, and 62's to about 2750. I could probably push it a good bit further, but I really don't see a point to doing so. Big +1 on that... Attempting to duplicate M193 velocity with canister-grade powders and non-crimped primers is a recipie for unpleasantness. |
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Attempting to duplicate M193 velocity with canister-grade powders and non-crimped primers is a recipie for unpleasantness.
How so? Ramshot and Accurate both list data that equals or exceeds M193 and M855 velocities and still stays within acceptable pressures. What does a crimped primer have to do with pressure? |
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Attempting to duplicate M193 velocity with canister-grade powders and non-crimped primers is a recipie for unpleasantness.
How so? Ramshot and Accurate both list data that equals or exceeds M193 and M855 velocities and still stays within acceptable pressures. What does a crimped primer have to do with pressure? Admittedly, those loads are on the ragged edge, but they do list 5.56mm data for some powders, TAC being the most notable. Pushing a 77 grain SMK at 2800 fps in a 20" barrel still leaves me decent brass life (about 5 firings with the LC brass, three with Winchester) and the issue with uncrimped primers is reliability, in that a primer can pop out of the case and gum up the works of the rifle. This takes a few loadings to happen, as the hot loads make the primer pocket progressively looser. |
| Don't make a poor bullet choice in some misguided effort to reach a magic velocity number. You might be able to get there with some 40-50gr varmint bullet, but you're going to be left with a crappy self-defense load. You're better off using a light TSX bullet, those will expand down to 1800 or so FPS. "Varmint grenade" type bullets have pathetic penetration, certainly insufficient for home/self-defense use. |
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Attempting to duplicate M193 velocity with canister-grade powders and non-crimped primers is a recipie for unpleasantness.
How so? Ramshot and Accurate both list data that equals or exceeds M193 and M855 velocities and still stays within acceptable pressures. What does a crimped primer have to do with pressure? Look at the barrel length that they use. Most load data uses at least a 20" barrel for their velocity. The crimped primer keeps the pressure for popping the primer out of the case thereby preventing damage to the bolt and / or firing pin. |
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