Request for Recipe (.223 77gr HPBT), also info to share

[1lostinspace]

I got great results with 77SMK winchester brass and 24 gr TAC COL 2.26

[Californio]

Win M70 26" CM barrel 1x9 twist

Hornady 75gr HPBT Match, Lapua brass, Federal 205 primer, 25.0gr. Varget

COAL 2.255

SMK 69gr, Lapua brass, Federal 205 primer, 25.1gr. Varget

COAL 2.255

The SMK is better than FGMM at 100 yards, I need to compare at 200 yards.

HPBT is on par with FGMM.

All under a dime.

I used the Hodgdon data it is a little more aggressive than the bullet makers data.

Primers look OK, I worked up slowly in .5 stages. Please start at the bottom and work up slowly.

[ar15barrels]

Cartridge          : .223 Rem. (SAAMI)
Bullet             : .224, 55, Hornady FMJ-BT w/c 2267
Cartridge O.A.L. L6: 2.250 inch or 57.15 mm
Barrel Length      : 16.0 inch or 406.4 mm

Predicted Data for Indicated Charges of the Following Powders.

Matching Maximum Pressure: 55000 psi, or 379 MPa

or a maximum loading ratio or filling of 105 %

These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

33 loads produced a Loading Ratio below user-defined minimum of 80%. These powders have been skipped.

Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
IMR 3031                           105.0     26.4     1.71    3076    97.9    53624   15803   0.779  ! Near Maximum !
Winchester 748                      99.0     28.0     1.81    3058    94.3    55000   15952   0.771  !DANGEROUS LOAD-DO NOT USE!
Accurate No.2520                   101.2     28.3     1.83    3042    95.4    55000   15836   0.786  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H322                        96.8     25.4     1.65    3039    97.3    55000   14909   0.771  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H335                        96.1     27.4     1.78    3027    95.2    55000   15397   0.775  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 10                   93.5     26.2     1.70    3025    96.2    55000   15123   0.779  !DANGEROUS LOAD-DO NOT USE!
Alliant Reloder-10x                 91.6     24.1     1.56    3023    99.4    55000   14265   0.785  !DANGEROUS LOAD-DO NOT USE!
Hodgdon BL-C2                       99.6     28.4     1.84    3023    93.2    55000   15796   0.783  !DANGEROUS LOAD-DO NOT USE!
Ramshot X-Terminator                94.5     25.8     1.67    3022    97.1    55000   14893   0.780  !DANGEROUS LOAD-DO NOT USE!
Ramshot TAC                         99.6     27.4     1.78    3015    93.3    55000   15371   0.778  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 9                   103.9     28.2     1.83    3005    91.2    55000   15451   0.777  !DANGEROUS LOAD-DO NOT USE!
IMR 4320                           105.0     28.0     1.82    3005    90.6    54967   15283   0.768  !DANGEROUS LOAD-DO NOT USE!
Accurate XMR 2015                  102.3     25.1     1.63    3002    99.0    55000   14214   0.790  !DANGEROUS LOAD-DO NOT USE!
IMR 4198                            93.2     22.6     1.46    2998    99.8    55000   13153   0.765  !DANGEROUS LOAD-DO NOT USE!
Alliant Reloder-12                  99.1     26.5     1.72    2997    97.3    55000   14514   0.777  !DANGEROUS LOAD-DO NOT USE!
Accurate XMR 2495                  105.0     26.4     1.71    2997    98.0    51022   15608   0.834  ! Near Maximum !
Accurate No.2460                    99.1     27.4     1.78    2995    94.4    55000   15091   0.794  !DANGEROUS LOAD-DO NOT USE!
IMR 4895                           105.0     27.0     1.75    2993    92.1    52401   15376   0.780  ! Near Maximum !
Hodgdon VARGET                     103.2     27.2     1.76    2985    91.3    55000   14904   0.773  !DANGEROUS LOAD-DO NOT USE!
Accurate No.2230                    96.2     26.9     1.74    2985    94.3    55000   14762   0.790  !DANGEROUS LOAD-DO NOT USE!

[Jicko]

Thanks R, you are just such a valuable resource for the CG community!


PS. no "Reloader 15"???? I *know* that RL15 is probably too slow, and it is probably not the best or even suitable for 55gr-ers...... but I would expect, at least, being able to use it sub-optimally..... (i would expect Rl15 to be along the line with VARGET)


PPS.
I tested 5 rounds of each of 25gr of RL15 and VARGET (just seated, uncrimped)
RL15 gave me an avg MV of 2833fps
VARGET gave me an avg MV of 2757fps

This is along the line of what is listed on Sierra's 223 for AR loadmap:
http://accurateshooter.net/Downloads/sierra223ar.pdf

Now, I just want to know what's the max of RL15 I can push..... but I am having a HARD time finding data... (there is only 1 reference of using 27.0gr of RL15 for a 55gr bullets, and I am VERY RELUCTANT to test that.....)

I am more willing to just crimp the bullet and see if that can increases my MV, and just make my rounds as-is (or at most up the powder by 1gr to 26.0gr + crimp).... I weren't expecting too much accuracy out of these "plinking" 55gr-ers (golden-west-brass/montana-gold) anyways... I am just IN-NEED of 2k plinking rounds for a tac class immediately....

[ar15barrels]

Originally Posted by Jicko

PS. no "Reloader 15"???? I *know* that RL15 is probably too slow, and it is probably not the best or even suitable for 55gr-ers...... but I would expect, at least, being able to use it sub-optimally..... (i would expect Rl15 to be along the line with VARGET)


PPS.
I tested 5 rounds of each of 25gr of RL15 and VARGET (just seated, uncrimped)
RL15 gave me an avg MV of 2833fps
VARGET gave me an avg MV of 2757fps

This is along the line of what is listed on Sierra's 223 for AR loadmap:
http://accurateshooter.net/Downloads/sierra223ar.pdf

Now, I just want to know what's the max of RL15 I can push..... but I am having a HARD time finding data... (there is only 1 reference of using 27.0gr of RL15 for a 55gr bullets, and I am VERY RELUCTANT to test that.....)

The list is sorted by the top velocity producers.
I only grabbed the top 20 as there's no need to go further down the list to find a good load.

RL15 is too slow.
RL10 is more appropriate.
You can't get enough reloader 15 into the case to cause pressure problems with typical 55gr fmj-bt type bullets.

QL estimates 2825fps for 25gr of RL15 and 2894fps for 25gr of Varget in a 20" barrel.
QL estimates the max charge of RL15 to be 27.5, but that's not a high pressure charge.
That's simply 105% of case capacity.
If you could get it to fit, QL estimates 28.13gr of RL15 to produce 55,000psi behind a 55gr fmj-bt.

[Jicko]

Again, thanks R..... I need to "make work" whatever I have on hand.... rather than on my mission to find the "best" load this time.... kinda special this time...

Thanks for helping out....

I need 1k to 2k rounds in 2weeks.... I won't have enough time to do any ordering....

[ETD1010]

Looks like I can put my WIN 748 to good use on 55gr bullets as well... Now I'll just have to save my Varget for my .308 loads since 748 seems to do well for 77 gr. as well.



edit: I thought WIN 748 was a slower powder for .30-30 and the like...

[Jicko]

I am changing my plan....

I am gonna use IMR-4198 and CCI #41 primers....

[Darklyte27]

Unfortunetly I was having issues with my Rings on my Stag 6L. shots were way to the left, Leupold rings are coming tomorrow. I didnt shoot it as much as I shot my Savage. I had a blast with that, some sub moa shots too through the same hole.

I got some SMK 69 gr to test out.
hopefully I can get out this or next week.

Sucky part is that I only have #41 primers

[Darklyte27]

aiyaiyai, got a YHM Riser mount. first shot was way right!! must have been when I adjusted the scope from last time..
anyways, Heres a thread I started with pics of what I shot with the varminter and 308 today. Slight wind at 5-8 mph or so..
Pics 4 and 5 were my reloads, I forgot to take a picture of another set of shots with my reloads but they were ok, nothing much to brag about.

http://www.calguns.net/calgunforum/s....php?p=2139473

[Jicko]

Originally Posted by Jicko

I am changing my plan....

I am gonna use IMR-4198 and CCI #41 primers....

Bad idea.... *sigh*.... stay tuned for more info

[Linus]

Originally Posted by Jicko

Bad idea.... *sigh*.... stay tuned for more info

Short-stroked on ya?

[Darklyte27]

must be the powder?..

i am using #41 primers too cuz thats all i have so it sucks..
I am still waiting for small rifle benchrest or plain primers...

[Jicko]

Great info -> http://www.ar15.com/forums/topic.html?b=3&f=16&t=406469

I will add it to the first post too!!

[Darklyte27]

verrr naiiiice

[Linus]

Randall, could you please post the Quickload specs but for Hornady's 75gr HPBT in a 18" barrel with a 1:8" twist.
Thanks in advance.
~Linus

Originally Posted by ar15barrels

Cartridge          : .223 Rem.
Bullet             : .224, 77, Sierra HPBT MatchK 9377
Cartridge O.A.L. L6: 2.250 inch or 57.15 mm
Barrel Length      : 18.0 inch or 457.2 mm

Predicted Data for Indicated Charges of the Following Powders.

Matching Maximum Pressure: 55000 psi, or 379 MPa

or a maximum loading ratio or filling of 105 %

These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

36 loads produced a Loading Ratio below user-defined minimum of 80%. These powders have been skipped.

Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
IMR 3031                           100.0     23.1     1.49    2730   100.0    55000   11635   0.952  ! Near Maximum !
SNPE Vectan SP 11                  105.0     26.1     1.69    2721    96.1    54711   12715   0.948  ! Near Maximum !
IMR 4895                           101.7     24.0     1.55    2718    98.0    55000   12096   0.937  ! Near Maximum !
Winchester 748                      94.1     24.4     1.58    2718    98.5    55000   12120   0.950  ! Near Maximum !
Alliant Reloder-15                 102.0     24.6     1.59    2702    95.8    55000   12375   0.959  ! Near Maximum !
Accurate XMR 2495                  101.1     23.3     1.51    2702   100.0    55000   11505   0.990  ! Near Maximum !
Accurate No.2520                    96.0     24.7     1.60    2699    99.0    55000   11911   0.968  ! Near Maximum !
SNPE Vectan Sp 7                   101.9     26.3     1.70    2698    95.8    55000   12424   0.956  ! Near Maximum !
Hodgdon BL-C2                       94.8     24.9     1.61    2692    97.7    55000   12133   0.963  ! Near Maximum !
Vihtavuori N150                    102.9     24.5     1.59    2692   100.0    55000   11409   0.958  ! Near Maximum !
IMR 4320                           100.4     24.6     1.59    2686    96.1    55000   11927   0.944  ! Near Maximum !
Hodgdon H335                        91.4     23.9     1.55    2684    98.9    55000   11679   0.956  ! Near Maximum !
Ramshot TAC                         94.8     24.0     1.55    2679    97.8    55000   11785   0.958  ! Near Maximum !
Accurate XMR 4064                  105.0     24.5     1.59    2679    99.5    53112   11959   1.001  ! Near Maximum !
SNPE Vectan SP 9                    99.0     24.7     1.60    2679    96.3    55000   11985   0.956  ! Near Maximum !
Hodgdon H322                        91.8     22.1     1.43    2678    99.8    55000   11080   0.953  ! Near Maximum !
SNPE Vectan SP 10                   88.8     22.9     1.48    2675    99.4    55000   11366   0.961  ! Near Maximum !
Vihtavuori N135                    102.8     23.7     1.54    2671   100.0    55000   10900   0.964  ! Near Maximum !
Vihtavuori N550                    105.0     26.4     1.71    2667    93.2    50994   12827   0.983
Ramshot X-Terminator                89.7     22.4     1.45    2667    99.7    55000   11103   0.962  ! Near Maximum !
Accurate No.2460                    94.2     23.9     1.55    2657    98.5    55000   11434   0.977  ! Near Maximum !
Winchester 760                     105.0     26.7     1.73    2657    89.5    51389   12711   0.975
Hodgdon VARGET                      98.4     23.8     1.55    2656    96.4    55000   11578   0.954  ! Near Maximum !
IMR 4064                           101.2     23.9     1.55    2656    95.8    55000   11576   0.957  ! Near Maximum !
Vihtavuori N140                    101.2     23.9     1.55    2656    99.6    55000   11068   0.960  ! Near Maximum !
Ramshot BigGame                    105.0     25.5     1.65    2649    94.9    50238   12363   0.986
Accurate No.2230                    91.5     23.5     1.52    2646    98.4    55000   11202   0.973  ! Near Maximum !
Alliant Reloder-12                  94.2     23.2     1.50    2646    99.8    55000   10830   0.959  ! Near Maximum !
Alliant Reloder-10x                 86.7     20.9     1.35    2646   100.0    55000   10309   0.970  ! Near Maximum !
Accurate XMR 2015                   96.9     21.8     1.41    2634   100.0    55000   10315   0.976  ! Near Maximum !
Hodgdon H414                       101.9     26.4     1.71    2633    86.6    55000   12065   0.964  ! Near Maximum !
Vihtavuori N540                     99.3     25.0     1.62    2631    96.4    55000   11523   0.965  ! Near Maximum !
Accurate 2200                       83.6     21.3     1.38    2627    99.0    55000   10616   0.959  ! Near Maximum !
Hodgdon Benchmark                   94.4     22.5     1.46    2624    98.4    55000   10844   0.962  ! Near Maximum !
Vihtavuori N133                     96.0     22.1     1.44    2610   100.0    55000    9976   0.962  ! Near Maximum !
IMR 4198                            88.3     19.7     1.27    2609   100.0    55000    9471   0.953  ! Near Maximum !
Hodgdon H4895                       97.2     23.2     1.50    2604    96.7    55000   10786   0.960  ! Near Maximum !
Vihtavuori N130                     91.3     21.3     1.38    2598   100.0    55000    9748   0.969  ! Near Maximum !
Hodgdon H4198                       89.3     19.9     1.29    2593    99.7    55000    9804   0.955  ! Near Maximum !
Ramshot Hunter                     105.0     27.0     1.75    2593    89.2    47768   12482   1.008
Hodgdon H380                       105.0     26.1     1.69    2579    87.5    49685   11973   1.006
Accurate No.2700                   102.7     26.1     1.69    2576    89.4    55000   11047   0.971  ! Near Maximum !
Vihtavuori N120                     85.8     19.6     1.27    2555   100.0    55000    8733   0.973  ! Near Maximum !
Alliant Reloder- 7                  80.0     18.9     1.22    2550   100.0    55000    8889   0.996  ! Near Maximum !
IMR 4227                            83.4     18.1     1.17    2549   100.0    55000    8679   0.958  ! Near Maximum !
Hodgdon H4227                       81.8     17.7     1.15    2539   100.0    55000    8458   0.963  ! Near Maximum !

[ar15barrels]

Originally Posted by Linus

Randall, could you please post the Quickload specs but for Hornady's 75gr HPBT in a 18" barrel with a 1:8" twist.
Thanks in advance.
~Linus

Cartridge          : .223 Rem. (SAAMI)
Bullet             : .224, 75, Hornady BTHP M 2279
Cartridge O.A.L. L6: 2.260 inch or 57.40 mm
Barrel Length      : 18.0 inch or 457.2 mm

Predicted Data for Indicated Charges of the Following Powders.

Matching Maximum Pressure: 55000 psi, or 379 MPa

or a maximum loading ratio or filling of 105 %

These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

36 loads produced a Loading Ratio below user-defined minimum of 80%. These powders have been skipped.

Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
IMR 3031                           100.4     23.4     1.52    2769   100.0    55000   11841   0.941  !DANGEROUS LOAD-DO NOT USE!
Winchester 748                      94.4     24.8     1.60    2754    98.3    55000   12306   0.939  !DANGEROUS LOAD-DO NOT USE!
IMR 4895                           102.0     24.3     1.58    2754    97.8    55000   12271   0.927  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 11                  105.0     26.4     1.71    2747    95.7    54176   12845   0.942  ! Near Maximum !
Accurate XMR 2495                  101.5     23.7     1.53    2740   100.0    55000   11712   0.979  !DANGEROUS LOAD-DO NOT USE!
Alliant Reloder-15                 102.3     24.9     1.62    2738    95.5    55000   12546   0.948  !DANGEROUS LOAD-DO NOT USE!
Accurate No.2520                    96.3     25.0     1.62    2735    98.9    55000   12099   0.957  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan Sp 7                   102.2     26.7     1.73    2733    95.5    55000   12594   0.945  !DANGEROUS LOAD-DO NOT USE!
Vihtavuori N150                    103.3     24.9     1.61    2729    99.9    55000   11602   0.947  !DANGEROUS LOAD-DO NOT USE!
Hodgdon BL-C2                       95.1     25.2     1.63    2727    97.5    55000   12309   0.952  !DANGEROUS LOAD-DO NOT USE!
IMR 4320                           100.6     24.9     1.62    2721    95.8    55000   12088   0.934  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H335                        91.6     24.3     1.57    2721    98.8    55000   11857   0.945  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H322                        92.1     22.4     1.45    2715    99.8    55000   11264   0.942  !DANGEROUS LOAD-DO NOT USE!
Ramshot TAC                         95.0     24.3     1.57    2715    97.6    55000   11956   0.947  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 9                    99.3     25.0     1.62    2714    96.1    55000   12150   0.945  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 10                   89.1     23.2     1.50    2712    99.3    55000   11546   0.949  !DANGEROUS LOAD-DO NOT USE!
Vihtavuori N135                    103.1     24.0     1.56    2708   100.0    55000   11092   0.952  !DANGEROUS LOAD-DO NOT USE!
Accurate XMR 4064                  105.0     24.8     1.60    2706    99.3    52498   12125   0.995  ! Near Maximum !
Ramshot X-Terminator                90.0     22.8     1.47    2704    99.7    55000   11284   0.950  !DANGEROUS LOAD-DO NOT USE!
Accurate No.2460                    94.5     24.3     1.57    2693    98.3    55000   11608   0.966  !DANGEROUS LOAD-DO NOT USE!

[Gnzrme]

Did anybody do the 55gr tests...

[Darklyte27]

Gnzrme, probably not in this thread since this is mainly for Match type ammo.. 69+ grain bullets.

usually 55 gr is for plinking and casual range shooting. Is there something specific you are looking for?

[Gnzrme]

yes, I guess I am looking for plinking loads, but also, I have a 1:9 twist bbl and will probably start loading SMK's 69gr's...only have one # of varget.

Also, I have a 1 # can of apparently discontinued Vhitavouri v170 powder, can I use this for 223..?

[Darklyte27]

1/9 barrel is good for 55 and 62 gr.
anything heavier wont shoot right because 1/9 is not fast enough twist for heavier bullets.

69+ gr you want at least 1/8 to 1/7

for plinking rds, you want to look for a cheaper powder for plinking rds.

H335, reloader15, Ramshot tac, winchester 748 and a few others.
Varget is pretty expensive for plinking rds. You want to save that for match type ammo.

I cant help ya with the vhitavouri stuff.

[ar15barrels]

Originally Posted by Darklyte27

1/9 barrel is good for 55 and 62 gr.
anything heavier wont shoot right because 1/9 is not fast enough twist for heavier bullets.

69+ gr you want at least 1/8 to 1/7

WRONG.

69gr SMK or 68gr Hornady work great in 1:9 twist barrels.
If you have a 20" long 1:9 barrel, you can usually get 75gr Amaxes to work too.

A 16" or 14.5" 1:9 barrel usually won't stabilize the 75's though because it does not make enough velocity so the 69's are the max there.

[Darklyte27]

Im not wrong, im just not 100% right haha Your CAPSLOCK KEY GET STUCK?

I was ball parking it with this link
http://ammo.ar15.com/ammo/project/perf_whattwist.html

[ar15barrels]

Originally Posted by Darklyte27

Im not wrong, im just not 100% right haha Your CAPSLOCK KEY GET STUCK?

I was ball parking it with this link
http://ammo.ar15.com/ammo/project/perf_whattwist.html

So you missed this part?

At typical .223 velocities, a 1:9 twist will stabilize bullet lengths equivalent to lead-core bullets of 40 to 73 grains in weight.

What that article does not tell you is that the tolerance for most standard grade factory barrels is +/- 1/2" on the twist rate.
Therefore, a 1:9" barrel can vary from 1:8.5" to 1:9.5" and still be called a 1:9" twist barrel.
The 1:8.5" barrels will certainly stabilize the 75 Amaxes while the 1:9.5" barrels won't.

[ar15barrels]

Originally Posted by Darklyte27

Im not wrong, im just not 100% right

Ok, let's count the ways...

Originally Posted by Darklyte27

1/9 barrel is good for 55 and 62 gr.
anything heavier wont shoot right because 1/9 is not fast enough twist for heavier bullets.

69+ gr you want at least 1/8 to 1/7

for plinking rds, you want to look for a cheaper powder for plinking rds.

H335, reloader15, Ramshot tac, winchester 748 and a few others.
Varget is pretty expensive for plinking rds. You want to save that for match type ammo.

I cant help ya with the vhitavouri stuff.

The incorrect statements are in red.
You were right about using cheaper powders for plinking though.

[ryochiji]

This weekend, I shot Nosler 77gr HPBTs in a service rifle match. LC brass, 24.0gr TAC, CCI 450, COAL 2.260", chronographed at 2740fps out of my 1-8 twist 20" barrel. With a 200 yard zero, my come-ups were 2 MOA at 300 yards, 11 MOA at 600 yards.

[bartt]

Originally Posted by ar15barrels

So you missed this part?



What that article does not tell you is that the tolerance for most standard grade factory barrels is +/- 1/2" on the twist rate.
Therefore, a 1:9" barrel can vary from 1:8.5" to 1:9.5" and still be called a 1:9" twist barrel.
The 1:8.5" barrels will certainly stabilize the 75 Amaxes while the 1:9.5" barrels won't.

I'd like to take this a bit farther..
I am running a 24" 1:9 SS bull barrel and wonder if the length of the barrel doesn't also have some affect on this? IOW, given all else is equal would a longer barrel stabilize a 77 - 80 gr bullet better than a shorter barrel?
Intuition tells me it would, but that may not hold any water..
TIA for any insight.

[Jicko]

Originally Posted by bartt

I'd like to take this a bit farther..
I am running a 24" 1:9 SS bull barrel and wonder if the length of the barrel doesn't also have some affect on this? IOW, given all else is equal would a longer barrel stabilize a 77 - 80 gr bullet better than a shorter barrel?
Intuition tells me it would, but that may not hold any water..
TIA for any insight.

Just go try it. I have a 1:9 24" SS bull upper that will do 77gr SMK without any issue....

[ar15barrels]

Originally Posted by bartt

I am running a 24" 1:9 SS bull barrel and wonder if the length of the barrel doesn't also have some affect on this? IOW, given all else is equal would a longer barrel stabilize a 77 - 80 gr bullet better than a shorter barrel?

Velocity is a factor in the stabilization formula.
Longer barrels make more velocity.
Therefore, given the same cartridge and loading, longer barrels do not need to have as fast of a twist rate to stabilize the same length bullets.

Depending on the tolerances of YOUR barrel and YOUR load, YOUR barrel may or may not stabilize 77-80gr bullets.
The way to find out is to go shoot them through YOUR barrel.

I recommend doing this testing at the lowest altitude and on the coolest day you may ever shoot them as higher altitude and warmer weather also help stabilization.

[bartt]

Originally Posted by ar15barrels

Velocity is a factor in the stabilization formula.
Longer barrels make more velocity.
Therefore, given the same cartridge and loading, longer barrels do not need to have as fast of a twist rate to stabilize the same length bullets.

Depending on the tolerances of YOUR barrel and YOUR load, YOUR barrel may or may not stabilize 77-80gr bullets.
The way to find out is to go shoot them through YOUR barrel.

I recommend doing this testing at the lowest altitude and on the coolest day you may ever shoot them as higher altitude and warmer weather also help stabilization.

Thanks for the feedback.
Since I live and play at 3000 ft and higher, this could get interesting (in a good way)

[whiskey08]

les baer .223 police special
16 inch barrel with 1 in 8 twist
77gr sierra hpbt match
coal 2.255


average of 5 rounds using chrony chronograph, my goal was to hit 2,750 fps this would give me a max spread of 4 inches from 0 - 250yrds if I zero at 50 yards. Also will give me a frag range of close to 200 yrds.

elev = 5,000ft
temp = 75 degrees


lapua brass
cci br-4
26 gr tac = 2,740fps

privi brass
cci br-4
26 gr tac 2,740fps

privi brass
already primed with privi primer
25.7 tac = 2,740

no signs of excessive pressure on anywhere on cases

the privi brass is not as consitent as the lupua, and in every string there is a flyer, I think because my RCBS electronic scale keeps changing its zero.

[whiskey08]

couple of additions to my last post

spread from 0 -250 supposedly will be 4.9inches as per software posted on internet

tap 75gr
2341fps -2455fps

gonna go back to range and work on grouping, zero, and differnces of point of impact for different types of brass, will post feedback

[Ahhnother8]

Accuracy / bullet stability with regard to barrel twist / velocity / bullet weight:

Research is in progress using a standard .223 cartridge firing 90 grain bullets. These have been out for quite some time, but almost nobody has been successful in getting them to work better than the 80 grain bullets. Most used 1:6.5" twist barrels, as according to "the experts" anything slower would result in tumbling bullets. This research is being done with a 1:7.7" twist barrel, and the bullets are stable above 2850 fps, out to 1000 yards. They also have less wind drift than a .308, using 155 grain bullets at 3000 fps.

Just another option for those shooting any .22 bore.

[Darklyte27]

is the only diff between mod 0 and 1 is the Cannelure?

[ar15barrels]

Originally Posted by Darklyte27

is the only diff between mod 0 and 1 is the Cannelure?

If you are talking about Mk262, then that's the only difference that matters.

[Darklyte27]

thanks randall, so is one better than the other?

[Darklyte27]

alright, i finally got some CCI #400s.

I loaded 10 rds with #41, 5 with wolf sr, and 5 #400's

Brass New LC 08
Various primers listed, no BR primers.
Powder Varget at 24 gr
Bullet 69 gr SMK
COAL 2.26

Will use my Stag 6HL varminter 20" 1:8 twist this coming sunday, will post results. I also just got some 77 gr SMKs but havent loaded yet.

[happysingleman]

I've had good luck with these links


Reloading Charts:
http://data.hodgdon.com/main_menu.asp

Components:
http://powdervalleyinc.com/

Powder Burn Rates:
http://www.reloadbench.com/burn.html

[ETD1010]

Has anyone tried using WIN 748 for the 77 grainers? I keep seeing computer generated results that shows them at the top of the velocity scale with 25 grains worth. I'm currently out of my SR primers so I can't check it yet. I have 500 fresh IMI cases that I want to load up 77s in. But until I do, I'm just researching the crap out of the different loads people are using.

[ocabj]

Unless you already have Win 748, stick with one of the big three:

Varget
RL15
N140

748 was more popular for lighter loads from 69gr on down.