Norma 223 Remington Brass Cases Compared to Lapua, PPU and Lake City
This is a review of two Norma 223 Remington brass cases available in the USA. One is Norma 223 Remington High Performance cases (Product number 202257212). The other is primed Norma brass available from Powder Valley, Inc. (SKU: NOR121201893). This study was stimulated during the process of my selecting a 223 Remington cartridge case to use in working up a 600 yard load for one of my bolt-action target rifles. I normally use Lapua match cases for my match target rifles. However, at the time of needing cases, Lapua cases were unavailable. I compared the Norma brass cases with other 223 brass I had on hand: Lapua, PPU PRVI Partizan, and Lake City brass in hopes of finding a substitute case for Lapua cases I had been using in my match 223 Remington rifles.
Brass Cases Tested:
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Norma Brass
Headstamp of Norma Primed and Norma High Performance Brass. |
Study Procedures
1. Brass cases were initially tested following removal from the shipping box or bag from the supplier. Unprocessed (virgin) brass was used in all instances except for the Lake City brass which was once-fired military 5.56x45mm NATO brass which had been reconditioned to 223 Remington cases (deprimed, swagged, resized, trimmed and cleaned/polished) by Top Brass, LLC.
2. Cases were measured, loaded and fired
with the same standard load except where noted: 77gr Sierra MatchKing, 23.0gr AR-Comp, GM205M primer, 2.35" COAL. The bolt-action rifle had a 28 inch Krieger 1:7.7 twist barrel with a 223 Wylde chamber
3.
Fired cases were deprimed, cleaned, and necks were annealed. Resizing was done by: A) Neck sizing only; or B) Full length resizing with a small base die. Cases were gauged, remeasured, loaded with the standard load and refired.
4. Virgin Norma Primed brass was tested with different primers to determine that the primer in the primed cases was a small rifle magnum primer.
5. Durability of Norma Primed brass was tested by running 8 reloading
cycles on the brass after firing to examine for neck wall splitting and loosening of primer pockets.
6. Accuracy of match rifles loaded with cartridges made using Norma
Primed and Norma High Perfornance brass was tested using two .223 Remington bolt-action rifles.
Details of the methods study procedures 1 through 4 are: HERE.
Case Weight (all brass without primers):
Cases from Norma Primed brass are the heaviest case of those tested (p<0.001, ANOVA.). Lake City brass was the lightest.
Case Volume Capacity:
Cases from Norma Primed brass have the smallest volume capacity of all the cases tested. (p<0.05, ANOVA). Lake City and Norma High Performance brass have the highest.
Case Neck Wall Thickness
Norma High Performance and Lapua cases have the thickest case neck walls. Norma primed brass has the thinnest case neck wall.
Loaded Case Neck Diameter with 77gr Sierra Match King Bullets
Reference data to use if you are selecting a bushing size to use with a neck-only resizing die.
Bullet Muzzle Velocity with Standard Load
Bullet muzzle velocity and variation for the various brass cartridges with the standard load. All ambient temperatures at firing were between 78 and 82 F, except Norma High Precision which was 55 F. The higher velocity at 55 F is most likely due to temperature-induced higher velocities with AR-Comp at temperatures below 60F.
Bullet Muzzle Velocity with Different Primers in Norma Brass Supplied as Primed Brass (SKU NOR121201893)
The data indicate that the primer in the Primed Norma brass is most likely a magnum small rifle primer.
Does the Thin Neck Wall of Norma Primed Brass(SKU NOR121201893) Affect Its Capacity To Be Reloaded?
Primed Norma brass studied had the thinnest neck walls of any of the brass studied. There was concern that this brass would be susceptible to neck wall splitting after only a few reloads. Lapua brass using my brass-reloading sequence can be reloaded at least 8 times before any neck splits occur (about 1 per 120 cases on the 9th reload cycle). Primed Norma brass was subjected to 9 firings with 8 full-length resizing and reload cyles without neck wall failures. The primer pockets remained tight to primer loading and retention. (Click HERE for details of firing/reloading procedures.) The findings indicate that Norma Primed brass is very tolerant of multiple reloading cycles.
Norma High Performance Brass and Primed Norma Brass Provided Excellent Accuracy for Match Loads in Bolt Action Rifles
Click on table below to enlarge for details.