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henryo

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About henryo

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  • Birthday 01/05/1992

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    Kent
  1. henryo

    N 150 versus N 550

    The double base powders have a less pronounced pressure peak than single base (occurs when the bullet is only a few inches down the barrel). If you then load to the same peak pressures, you will have a greater 'area under the curve' on a pressure vs time plot - which is the delta v or muzzle velocity. With a double base powder the best way to see it is you are using a slightly 'slower' (regressive) powder but it (normally) has a higher density letting you physically cram it all in the case. Hence more weight in grains for the same peak pressure, albeit a higher average pressure for a higher muzzle velocity. Obviously this is not 100% efficient so most of that extra energy is lost or goes in to the barrel... I think the naming convention Vihtavuori uses for N1XX vs N5XX are more about applicability for certain cartridges, than absolute burn rate
  2. henryo

    223 55gr load data

    RS40 is perfect for that combination Load Data
  3. henryo

    Bump shoulder back

    You will start to feel a bit of resistance when chambering the rounds, a little is ok in a bolt gun. Then use a body / FL die next time around. Use a headspace comparator and adjust to knock the shoulder back ~2 thou
  4. henryo

    .22-250 load advice

    It's doable if you have a chronograph to check velocitys and work up, but a bit on the fast side so have to be careful.
  5. henryo

    cz 527 COL

    Interesting as I've found factory barrels in general seem to have excessively long throats and I can't get anywhere near the lands with the bullet still having a good amount of bearing surface contact with the case neck. I think they do it to reduce the possibility of bullets being jammed in to the lands and producing pressure spikes with variable factory ammunition / dodgy reloads. You can still get very good accuracy with a long jump to the lands e.g. 100 thou or more but some bullets are more tolerant than others. I imagine the 60gr V-max is the classical tangent ogive and puts it fairly towards the tip hence shorter coal to lands. If you tried something like the 53gr v-max it would possibly work out longer. I would try at 1.855" as 20 thou is still enough tolerance that one won't end up touching the lands due to bullet variation. You probably won't notice a difference in accuracy anyway.
  6. henryo

    SWISS RS52

    Probably one of the best choices in a .223 with heavy bullets (69gr and up) If you're shooting 50 - 55gr RS40 has a more optimal burn rate and is again excellent
  7. henryo

    SAAMI Spec for 6.5x47 Lapua

    There is a drawing here: http://accurateshooter.net/Blog/65x47diagram.pdf
  8. henryo

    6 BR

    CCI 400 has a thinner cup I'd stick to 450 or BR4 (apparently hotter) in this cartridge or alternatively Rem. 7 1/2
  9. henryo

    .223 data

    Closest the vihtavuori website has is for 60gr bullet: 20.5gr start 23.1gr max Sierra data is showing data for 63gr bullet as 22.2gr max and 69gr bullet as 20.5gr! Quickload is showing 23gr for 55kpsi using my water capacity (warmish but normally brass life is still good) with 3000fps in a 24" barrel and 2900fps if you have the 20". 100% burn either way I'd probably start at 20.5gr maybe 21gr or so...
  10. henryo

    223 load data

    Benchmark is good Despite what people say about it being too fast I've had good results with IMR 4198, noticeably quieter I imagine it would work well in a 20" barrel Look up the starting data on the Hodgdon website
  11. henryo

    magnum primers in small cases - .222/.223?

    Yes I use CCI 450s for everything
  12. henryo

    7x57r loads

    Ok so with 140gr Bullets VV manual: http://www.vihtavuori.com/en/reloading-data/rifle-reloading/7-x-57r.html N150 Start 39gr Max 43.4gr More Data (Nosler): http://www.nosler.com/nosler-load-data/7x57mm-mauser/ N150 Start 39.5 Max 43.5gr R. Hunter Start 45.5gr Max 49.5gr and quickload: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Cartridge : 7 x 57 R Bullet : .284, 140, Sierra SPBT 1905 Cartridge O.A.L. L6: 3.071 inch or 78.00 mm Barrel Length : 26.0 inch or 660.4 mm Powder : Vihtavuori N150 Predicted data by increasing and decreasing the given charge, incremented in steps of 1.136% 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 -11.4 81 39.00 2407 1801 31044 6822 97.6 1.588 -10.2 82 39.50 2435 1843 32062 6903 98.0 1.568 -09.1 83 40.00 2463 1885 33113 6983 98.3 1.548 -08.0 84 40.50 2490 1927 34196 7059 98.6 1.528 -06.8 85 41.00 2517 1970 35314 7133 98.8 1.509 -05.7 86 41.50 2545 2013 36466 7203 99.1 1.490 -04.5 87 42.00 2572 2056 37655 7271 99.3 1.470 -03.4 88 42.50 2599 2100 38881 7336 99.5 1.447 -02.3 89 43.00 2626 2143 40146 7397 99.6 1.426 -01.1 91 43.50 2653 2187 41450 7456 99.7 1.405 +00.0 92 44.00 2679 2232 42796 7511 99.8 1.385 ! Near Maximum ! +01.1 93 44.50 2706 2276 44184 7562 99.9 1.365 ! Near Maximum ! +02.3 94 45.00 2732 2321 45616 7611 100.0 1.345 ! Near Maximum ! +03.4 95 45.50 2759 2366 47093 7656 100.0 1.326 ! Near Maximum ! +04.5 96 46.00 2785 2411 48618 7697 100.0 1.307 !DANGEROUS LOAD-DO NOT USE! +05.7 97 46.50 2811 2456 50192 7738 100.0 1.289 !DANGEROUS LOAD-DO NOT USE! +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Cartridge : 7 x 57 R Bullet : .284, 140, Sierra SPBT 1905 Cartridge O.A.L. L6: 3.071 inch or 78.00 mm Barrel Length : 26.0 inch or 660.4 mm Powder : Ramshot Hunter Predicted data by increasing and decreasing the given charge, incremented in steps of 1.0% 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 -10.0 86 45.00 2551 2023 33579 8021 92.6 1.509 -09.0 87 45.50 2579 2068 34618 8126 93.1 1.491 -08.0 87 46.00 2608 2114 35690 8229 93.6 1.474 -07.0 88 46.50 2636 2160 36796 8330 94.1 1.456 -06.0 89 47.00 2664 2207 37939 8429 94.6 1.433 -05.0 90 47.50 2693 2254 39118 8526 95.0 1.414 -04.0 91 48.00 2721 2302 40332 8620 95.5 1.394 -03.0 92 48.50 2749 2350 41593 8711 95.9 1.374 -02.0 93 49.00 2778 2398 42891 8800 96.3 1.355 ! Near Maximum ! -01.0 94 49.50 2806 2447 44232 8886 96.7 1.336 ! Near Maximum ! +00.0 95 50.00 2834 2497 45608 8969 97.0 1.318 ! Near Maximum ! +01.0 96 50.50 2862 2547 47051 9049 97.4 1.299 ! Near Maximum ! +02.0 97 51.00 2891 2597 48532 9126 97.7 1.281 ! Near Maximum ! +03.0 98 51.50 2919 2648 50062 9201 98.0 1.264 !DANGEROUS LOAD-DO NOT USE! +04.0 99 52.00 2947 2699 51644 9271 98.3 1.246 !DANGEROUS LOAD-DO NOT USE! +05.0 100 52.50 2975 2751 53283 9339 98.5 1.229 !DANGEROUS LOAD-DO NOT USE! You will probably want to check what kind of pressures are suitable for your rifle - the factory data might be on the mild side, so you don't blow up historic rifles.
  13. henryo

    8 twist 223 75 amax

    My accuracy load with the 75gr A-Max in a standard .223 is an unpostable amount of VV N140. Running 3070 fps in a 30" barrel.
  14. henryo

    Loose primers

    Reminds me of when my friend told be how to work up a load for Match Rifle: "Keeping working up until you start blowing primer pockets then back off 0.1gr"
  15. 26" to 20" will lose you ~150-200fps in a 223. Also 1gr of powder is normally ~100fps in a 223, maybe a bit more speed difference with light bullets. Personally I'd be looking to hit a theoretical accuracy node at 3200 - 3250 fps, which should be safe even with the shorter barrel (with lapua brass + thick cup primers), but will probably take you over factory 'max'.
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