Can someone run Quickload on these 5.56 loads?

[Telperion]

I've been working up an M855 clone and want to gauge how close these loadings are to the pressure limit.

Can someone with quickload run the numbers on these loads:

62 gr bullet (M855)
CCI 41 primer
COAL: 2.250"
Bbl length: 16"

Charge: a) 26.0 gr TAC, and b) 26.5 gr TAC

[f4tweet]

FWIW, my buddy shoots with H-335, and his listed max is 25.5. Very accurate.

[ar15barrels]

26.0gr of Tac is 53,643 psi and 2846 fps.
26.5gr of Tac is 57,065 psi and 2904 fps.

Cartridge          : .223 Rem.
Bullet             : .224, 62, IMI FMJBT M855
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: 62000 psi, or 427 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 !

50 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
---------------------------------  -----------------------------------------------------------------
Winchester 748                     100.7     27.7     1.79    3022    97.1    62000   15856   0.766  !DANGEROUS LOAD-DO NOT USE!
Accurate No.2520                   102.7     27.9     1.81    3001    97.9    62000   15618   0.781  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H322                        98.6     25.2     1.63    2993    99.2    62000   14682   0.767  !DANGEROUS LOAD-DO NOT USE!
Hodgdon BL-C2                      101.3     28.1     1.82    2989    96.2    62000   15771   0.777  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H335                        97.8     27.1     1.76    2989    97.8    62000   15297   0.771  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 10                   95.4     26.0     1.69    2985    98.4    62000   14990   0.774  !DANGEROUS LOAD-DO NOT USE!
Ramshot TAC                        101.5     27.2     1.76    2981    96.3    62000   15375   0.772  !DANGEROUS LOAD-DO NOT USE!
Ramshot X-Terminator                96.5     25.6     1.66    2979    99.0    62000   14709   0.774  !DANGEROUS LOAD-DO NOT USE!
IMR 3031                           105.0     25.6     1.66    2979    99.2    57245   15235   0.794  ! Near Maximum !
Alliant Reloder-10x                 93.6     23.9     1.55    2969   100.0    62000   13835   0.780  !DANGEROUS LOAD-DO NOT USE!

[Telperion]

Thanks Randall. Is 62,000 psi the pressure limit for 5.56mm? I've heard 52k, 55k, and 60k before.

I have tried the 26.0 gr load and it comes within 1% of the velocities I get from Lake City M855. I wonder if it's worth it to keep going for that last 1%.

[ar15barrels]

The NATO limit is just over 62K so I use 62K.
The SAAMI limit is 55K.