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Discussion in 'Reloading' started by darrindlh, Jul 15, 2011.
Am i expecting to much out of my 300 wm to try for 2800 fps with a 230grn.
I can't say for sure as I have never loaded 230's. But I feel you should be able to get there. It will depend on the rifle as all are different, but my sons 300 wm is sending 210 Bergers at just over 2900 and my 300wm is at 3000 with 210's. Both rifles have 28" Broughtons with 5C rifling and we are using Lapua brass and H-1000 powder. Neither rifle shows any sign of over pressure.
Hope this helps.
The reason i ask is the new mrk240 rounds are loaded with the sierra matchking 220grn and has a velocity of 2830fps. Don't know about the 230 grn berger how it will fly.
that's close if not a max load in the manuals (older ones mostly), and I think a lot it it depends on how the throat was cut. If it's a typical .300 Win mag throat I doubt it because you'll loose case volume with the bullet seated down into the shoulder. A .300 Weatherby would do it, and maybe a .308 Norma if it has a the long throat. The Winchester case seems best suited for 200 grain and lighter bullets with the shorter neck length
Sounds like a not so good of a goal. 230 gr bullet, 2800 fps definately is not a goal for a standard 300 WM. Use a larger case, and a twist rate that will support that long of a bullet.
My overall length is 3.6. I seat the bergers supper long. My intention is not to reach 2800. 2700 fps is more like it. Like mentioned the gov is loading 220 's at 2800. 2700fps prob, i think this would arrive like a hammer
I'd love to see their load data, as I think they must be running with 70K psi
Tricky pm me and i will send you the article and the reaserch how they choose the 220's
Tricky pm me your email address and i will email you the article and the reaserch how they choose the 220's
I'll get you one out this weekend. Reason I kinda wonder is that they show it in the twenty+ year old manuals, but things change in the last ten years or so.
I here ya. I was looking at my nosler number four and 68 grns of reloader22 yeilds 2757. And that is not pushin it at all. Retumbo and h1000 are not even on there.
I just got off hogdons website and there loading data. 81 grns of retumbo yeilds 2810fps. This is looking good!
my #26 Hogdons manual shows 77 grains of H1000 with a 225 grain bullet at 2880 fps using a 26" barrel. The the new Hornaday manual shows 70 grains of Magpro with a 220 grain bullet at 2650fps with a 25" barrel. I'd just about imagine that the .300 case would handle 72 grains of Magpro, and would be a very dense load leading to better accuracey. That powder was developed just for big overbore magnum rounds like the WSM family.
This is the information straight from the Neco.navy.mil PDF document:
3.1 Classification of characteristics. Where critical or major
characteristic requirements are listed in this specification, they
are annotated by a “C” or “M” and sequential reference number
starting with “1” for critical and “101” for major. The letter and
number are contained in parentheses. The main verbiage of the
requirement is then surrounded by brackets, “[ ]”. Minor
characteristic requirements contain no annotation. Reference DOD-
3.1.1 Critical characteristic. One that analysis indicates is
likely, if defective, to create or increase a hazard to human
safety or to result in failure of a weapon system or major system
to perform a required mission.
3.1.2 Major characteristic. One that analysis indicates is not
critical but is likely, if defective, to result in failure of an
end item to perform a required mission.
3.1.3 Minor characteristic. One that analysis indicates is
significant to product quality but is not likely, if defective, to
impair the mission performance of the item.
3.2 First Article. When specified in the solicitation (see 6.2g),
a sample shall be subjected to First Article inspection in
accordance with 4.2.
3.3 Government-loaned property. Government-loaned property (see
6.2e and 6.4) might be used for performing tests as specified in
Section 4 and Appendices A, B and C of this specification.
Government-loaned property shall be described in the contract where
3.4 Components. MK 248 MOD 1 cartridge components are the
projectile, the cartridge case, the propellant, and the primer.
The projectile for the MK 248 MOD 1 shall be
the 220 grain Sierra MatchKing® Hollow Point Boat Tail (HPBT)
bullet, commercial part number 2240, manufactured by Sierra
Bullets, (Drawing 53711-8330251). The bullet shall have a lead or
lead alloy core and copper or copper alloy jacket. The bullet
shall have a nominal weight of 220 grains, with a tolerance of ±0.5
grains. The bullet diameter shall be 0.3086-0.0005 inches. The
bullet shall be of the reverse drawn, Open Tip Match (OTM) type
capable of meeting the accuracy requirements as specified in
3.4.2 Cartridge case. The cartridge case shall be .300 Winchester
Magnum constructed of copper alloy in accordance with ASTM B19, and
shall not be plated. The cartridge case shall meet the external
dimensional requirements of ANSI/SAAMI Z299.4-1992. (C1) [A vent
hole shall be present in the primer pocket of the cartridge case].
126.96.36.199 Headstamp. The cartridge case headstamp marking shall
consist of the identification code of the manufacturer, last 2
digits of year of manufacture and the notation “300 WM” or “300 WIN
MAG” in accordance with drawing 53711-8330252.
3.4.3 Primer. The primer shall be a large match rifle primer,
non-corrosive, nickel-plated, boxer type, and shall be of lead-
styphnate type. The primer shall have a brass anvil and brass cup.
The primer shall be capable of meeting the ballistic requirements
3.4.4 Propellant. (C2) [Each cartridge shall contain Hodgdon
H1000 propellant.] The propellant loaded in this cartridge shall
contain flash reduction additives or coatings, and shall meet the
temperature stability and ballistic requirements detailed in
3.5.1 Cartridge assembly. The cartridge assembly shall be
manufactured and inspected in accordance with drawing 53711-
3.5.2 Primer seating depth. The primer shall be seated in the
cartridge case to a depth of (M101) [0.000 to 0.008 inch below the
face of the cartridge case head.] The primer shall not be staked
or crimped in place.
3.5.3 Cartridge overall length. (M102) [The nominal overall
length of the assembled cartridge shall be 3.500 inches maximum,
3.450 inches minimum] in accordance with drawing 53711-8330252.
The distance from the cartridge case head to the 0.300 inch
diameter datum on the projectile ogive shall be controlled to
within ± 0.010 inches. The nominal overall length and the distance
from the cartridge case head to the 0.300 inch diameter datum on
the projectile ogive of the assembled cartridge shall be
established, within the above limits, by the manufacturer to meet
3.5.4 Cartridge headspace. (M103) [The cartridge headspace shall
be 0.212 inches minimum, 0.220 inches maximum], in accordance with
drawing 53711-8330252. Cartridge headspace shall be measured from
the base of the cartridge case to the opposite surface of the belt
of the cartridge case.
3.5.5 Primed case sensitivity. Primed Case Sensitivity tests
shall be conducted on empty primed cases in accordance with 4.5.5.
Primed case sensitivity shall be as follows:
(C3) [The mean critical height minus two standard
deviations ( H -2σ) shall be 3.0 inches minimum.]
(M104) [The mean critical height plus four standard
deviations ( H +4σ) shall be 22.0 inches maximum.]
Cartridge ballistic performance.
3.6.1 Velocity. (M105) [The corrected average muzzle velocity of
the cartridges conditioned at 70° ± 5° Fahrenheit (F) shall be
2,850 ± 50 ft/sec. feet per second (fps)]. The standard deviation
of the corrected muzzle velocity at 70° ± 5° F shall not exceed 15
fps. This test shall be conducted in accordance with paragraph
3.6.2 Chamber Pressure. (M106) [The corrected average chamber
pressure shall not exceed 68,100 pounds per square inch (psi) at
70°F.] Neither the chamber pressure of an individual sample test
cartridge nor the average chamber pressure plus three standard
deviations of chamber pressure shall exceed 78,900 psi. This test
shall be conducted in accordance with paragraph 4.5.7.
3.6.3 Operational Temperature Stability (High and Low). The
velocity and pressure of sample cartridges conditioned and fired at
the temperature extremes specified below shall be in accordance
with 188.8.131.52 and 184.108.40.206.
a. Conditioned at 165°F - 5°F for not less than 2 hours
immediately prior to firing.
b. Conditioned at -20°F + 5°F for not less than 2 hours
immediately prior to firing.
220.127.116.11 Velocity. (M107) [The average corrected muzzle velocity
of the sample cartridges conditioned at -20°F shall not vary by
more than 75 fps from the average corrected muzzle velocity of the
sample cartridges conditioned at 165°F.]
18.104.22.168 Chamber Pressure. (M108) [The average corrected chamber
pressure of the sample cartridges conditioned at -20°F and 165°F
shall not exceed 71,500 psi.] Neither the chamber pressure of an
individual sample test cartridge nor the average chamber pressure
plus three standard deviations of chamber pressure shall exceed
22.214.171.124 300 yard accuracy. (M109) [The extreme spread of any
individual 10-shot group shall not exceed 4.5 inches at 300 yards.
The average extreme spread of ten, 10-shot groups shall not exceed
3.5 inches at 300 yards.]
126.96.36.199 600 yard accuracy. (M110) [The extreme spread of any
individual 10-shot group shall not exceed 9.0 inches at 600 yards.
The average extreme spread of ten, 10-shot groups shall not exceed
7.0 inches at 600 yards.] This test shall be conducted in
accordance with 4.5.8 and Appendix B, except that the range to
target shall be 600 + 1 yard. This test shall be conducted as part
of the First Article Sample or if a First Article Sample is not
part of the contract, as part of the first production lot of a new
3.6.5 Function and Casualty. (M111) [There shall be no weapon
stoppages due to the cartridge.] The cartridge shall meet all
function and safety requirements of Table I. Misfires shall be
considered separately in accordance with Table I. Function and
causality testing shall be conducted using the rifles as specified
in the contract.
Please read and note that 68K psi +- a good bit is what they are running and their COAL is like 3.5".... it is all there... read and enjoy.