GGG First Look

Photos and detailed measurements of GGG 'Imperial'.

Part 1: Photos and detailed measurements of GGG 'Imperial'.
Part 2: On the range, On Target and Over the Chrono.
Part 3: Components.
Part 4: Components - Brass.
Part 5: GGG: Gas! Gas! Gas!

The measurements:

1: COAL: Cartridge Overall Length
2: CBTO: Cartridge Base to Ogive
3: CHSD: Case head to shoulder datum (relative to SAAMI min chamber)
4: SDTO: Shoulder Datum to Ogive (relative)
5: RO: Runout
6: W: Weight


	GGG: 100 - GGG - 15						RUAG: 60PG
	COAL	CBTO	CHSD	SDTO	RO	W	COAL	CBTO	CHSD	SDTO	RO	W
	2.797	2.245	0.0005	0.012	0.0015	380.80	2.787	2.238	-0.0020	0.010	0.0050	378.42
	2.792	2.249	-0.0005	0.019	0.0025	380.60	2.784	2.234	-0.0020	0.006	0.0055	376.96
	2.793	2.247	-0.0005	0.017	0.0060	380.88	2.787	2.238	-0.0020	0.010	0.0025	378.66
	2.796	2.251	0.0010	0.019	0.0065	380.20	2.781	2.234	-0.0025	0.008	0.0060	378.86
	2.796	2.248	0.0000	0.017	0.0025	380.82	2.784	2.238	-0.0025	0.010	0.0020	378.12
	2.793	2.245	-0.0020	0.016	0.0060	380.82	2.780	2.234	-0.0020	0.006	0.0035	377.24
	2.796	2.246	0.0000	0.014	0.0020	380.70	2.783	2.239	-0.0020	0.011	0.0010	379.24
	2.796	2.250	0.0000	0.019	0.0030	380.66	2.784	2.233	-0.0020	0.006	0.0030	378.10
	2.794	2.246	0.0000	0.016	0.0030	380.12	2.786	2.237	-0.0020	0.009	0.0035	377.00
	2.796	2.246	0.0000	0.013	0.0040	380.32	2.784	2.235	-0.0015	0.006	0.0060	377.32
	2.796	2.249	-0.0010	0.017	0.0045	380.52	2.780	2.234	-0.0025	0.007	0.0030	377.60
	2.795	2.250	-0.0010	0.020	0.0035	379.88	2.787	2.238	-0.0030	0.011	0.0060	378.70
	2.797	2.243	0.0000	0.012	0.0060	380.48	2.783	2.234	-0.0010	0.006	0.0020	378.06
	2.796	2.245	0.0000	0.013	0.0035	380.66	2.787	2.233	-0.0020	0.010	0.0025	378.30
	2.796	2.244	-0.0005	0.012	0.0015	380.18	2.781	2.232	-0.0020	0.007	0.0015	377.62
	2.798	2.245	0.0000	0.014	0.0010	381.50	2.777	2.231	-0.0030	0.004	0.0005	377.76
	2.795	2.247	-0.0010	0.014	0.0005	380.12	2.786	2.236	-0.0020	0.008	0.0020	378.04
	2.796	2.246	0.0000	0.016	0.0030	385.04	2.781	2.233	-0.0030	0.007	0.0045	378.08
	2.795	2.245	0.0000	0.015	0.0020	380.12	2.784	2.237	-0.0025	0.010	0.0070	378.14
	2.798	2.247	0.0000	0.017	0.0030	380.60	2.784	2.233	-0.0030	0.006	0.0040	378.50

Min	2.7920	2.2430	-0.0020	0.0120	0.0005	379.8800	2.7770	2.2310	-0.0030	0.0040	0.0005	376.9600
Max	2.7980	2.2510	0.0010	0.0200	0.0065	385.0400	2.7870	2.2390	-0.0010	0.0110	0.0070	379.2400
ES	0.0060	0.0080	0.0030	0.0080	0.0060	5.1600	0.0100	0.0080	0.0020	0.0070	0.0065	2.2800
Mean	2.7956	2.2467	-0.0003	0.0156	0.0033	380.7510	2.7835	2.2351	-0.0022	0.0079	0.0036	378.0360
SD	0.0016	0.0022	0.0006	0.0025	0.0018	1.0747	0.0028	0.0024	0.0005	0.0021	0.0019	0.6170

	Comparison of SDs
	COAL	CBTO	CHSD	SDTO	RO	W
GGG SD	0.0016	0.0022	0.0006	0.0025	0.0018	1.0747
RUAG SD	0.0028	0.0021	0.0005	0.0021	0.0019	0.6170

GGG COAL (Cartridge Overall Length)

Overall length is as consistent as can be expected and close to the CIP maximum of 2.8" (or metric equivalent). It's strange that this value has a lower ES than the CBTO - maybe they seat them by the meplat, rather than the ogive.

GGG CBTO (Cartridge Base to Ogive)

Again, reasonably consistent.

GGG CHSD (Case head to shoulder datum)

This value is very well controlled, but a little on the high side when the target audience is a wide spectrum of often tight-chambered rifles. I would expect a few people to feel resistance to bolt closure, but probably nothing serious.

GGG STDO (Shoulder Datum to Ogive - relative)

Probably one of the most important measurements, since this determines the distance between the ogive and the lands at the moment of primer ignition. Pretty reasonable results.

GGG RO (Runout)

Here's where things go downhill a little. There were quite a few samples with ≥ 0.005" runout (highlighted). The wobble was clearly visible with the naked eye as they span. These might show resistance going in, or even worse, they may bind coming out if unloaded live, pulling the bullet in the process (I experienced this once with RUAG).

GGG W (Weight)

I wasn't going to measure the weight, since it is unlikely to tell us much. The results were interesting though. With the exception of 1 round the total weights were within a spread of 1 grain. With RUAG I expect a range of +/- 2 grains = 4 grains spread in the brass alone. Then along came one round nearly 5 grains higher than all the rest. You'll find out where the extra weight came from in part 3.

Comparison of SDs

GGG wins the COAL, but CBTO is a much more meaningful and important measurement, so it's a hollow victory. The rest of the prizes go to RUAG, with one notable exception: Runout. Surprisingly the RUAG runount was worse, both the maximum and the SD. Apart from that the RUAG dimensions are more consistent, but not by much.

Other observations:

Both manufacturers control the shoulder position well with similar SDs, but the means are quite different, with GGG bang on the minimum chamber dimension (0.000), while the RUAG shoulder is set back 0.002 in comparison. I wonder whether GGG are more familiar with spacious military chambers, while RWS are better acquainted with tight competition ones.

Jump:

In a given rifle GGG will have around 0.008" to 0.011" *less* jump than RUAG.

The box is much more compact than the bulky RUAG ones.

It even fits in an H83 ammo tin (or an MTM AC30, AC50 etc)

The batch number is on the inside of the flap. The first delivery includes 3 batches, 80, 90 and 100 (this one).

The Inner bit

Crimped primers. NRA headstamp.

Let's get measuring!

Next: Part 2: On the range, On Target and Over the Chrono.