Trying the Oryx chassis on the 12 FV 6.5mm Creedmoor

The following are the results shot with the 12 FV 6.5mm Creedmoor in the new Oryx stock in Northern Virginia on Thursday morning, August 22nd at 100 yards. Temperatures were from 75 to 85 degrees with winds from 3 to 5 mph. Altitude of the range is 250 feet above sea level.

During the sessions I interchanged this rifle with my Oryx stocked 12 FV .223 when the barrels in each rifle heated up. I never allowed the barrel temperature to exceed 135 degrees, measured on temperature strips affixed to the barrels of both rifles. The 6.5mm Creedmoor’s barrel temperature would rise from about 85 to 130 degrees after just 5 or 6 shots. The .223’s barrel temperature would rise from 85 to 130 degrees after from 13 to 15 shots.

I used H4350 powder with a three different 130 grain bullets – Sierra TMK #7430, Sierra TGK #4330, and Hornady ELD-M #26177 bullets. All the groups were shot with a NightForce 8-32x56mm Benchrest scope. All rounds were shot using Lapua brass and CCI BR-4 primers. All loads were set up to match the 12^th reflection time of 1.361 msec. which should be the ‘sweet spot’ for the 26-inch barrel with a 0.040 recessed crown. The alternative of using a 10^th reflection at 1.134 resulted in loads that were well over Pmax and the 14^th reflection was flirting with minimum loads. The action screws were torqued to 60 in.-lbs. prior to this session per the Oryx directions.

The load description field shows the powder and charge, the O.A.L., the trim length, and the bullet exit time from the 26-inch barrel.

# Grps.	Load Description	Bullet	Weight	Velocity	Average	Median	St Dev	1	2	3	4
3	H4350 41.6 gr 2.892 1.906 wf 1.361 * 75/76 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra TMK #7430	130	2724	0.304	0.316	0.032	0.268	0.328	0.376
4	H4350 40.8 gr 2.888 1.902 wf 1.361 * 79/80 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra TMK #7430	130	2724	0.319	0.306	0.035	0.293	0.304	0.307	0.370
3	H4350 41.6 gr 2.869 1.900 wf 1.361 * 83/82 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra TGK #4330	130	2726	0.328	0.228	0.048	0.281	0.328	0.376
4	H4350 41.4 gr 2.817 1.897 wf 1.361 * 85/85 deg. F. 60 in.-lbs. Oryx CCI BR-4	Hornady ELD-M #26177	130	2719	0.328	0.329	0.027	0.301	0.310	0.347	0.355
14					0.320	0.313	0.032

The combined results for the TMKs averaged 0.312 with a median of 0.307 and the standard deviation was 0.032.
It was coincidence that the TGK and ELD-M bullets both averaged 0.328.
The TGK had one good group and one bad group (one out of group round) around a group that was right on the average.
The ELD-M had a much more consistent group measurements, but the groupings on the target looked a bit more irregular, if that makes any sense.

Only the TMK #7430 bullets have been shot before with IMR4451 powder in the Oryx chassis.

The groups fired with the TGKs and ELD-M bullet with H4350 were 3 and 4 respectively versus the 22 for the TGKs with IMR4451 and 6 for the ELD-Ms with IMR4451. There were 11 groups shot with H4350 with the TMKs so far, versus 29 groups shot with IMR4451.

The difference in sample size makes conclusions very tentative. However, there is a difference even when comparing groups shot with the same NightForce scope and Oryx stock for about the same sample size.

Unfortunately, there were no groups shot with IMR4451 powder with the Oryx stock for the 130 grain TGK or ELD-M bullets. All previous rounds were shot with the factory plastic stock. I think comparisons of H4350 performance with the rounds fired with IMR4451 powder in the Factory plastic chassis probably would be misleading although the average group sizes are larger for the IMR4451 powder averages.

	H4350	IMR4451	Diff.
TMK	0.292	0.345	0.053

That amounts to a 15.5% reduction in group size for the H4350 powder compared to the IMR4451 group average.

The following are the results shot with the 12 FV 6.5mm Creedmoor in the new Oryx stock in Northern Virginia on Friday and Saturday mornings, September 2^nd at 100 yards. Temperatures were from 71 to 79 degrees with winds from 4 to 6 mph. Altitude of the range is 250 feet above sea level.

I decided to test the performance of H4350 powder with 130 grain Sierra TMK #7430, Sierra TGK #4330, Hornady ELD-M #26177 bullets as well as 142 SMK #1742 bullets so I could compare it to previous loads with IMR4451 powder shot in the Oryx Chassis. All the groups were shot with a NightForce 8-32x56mm Benchrest scope. All rounds were shot using Lapua brass and CCI BR-4 primers. All loads were set up to match the 12^th reflection time of 1.361 msec. which should be the ‘sweet spot’ for the 26-inch barrel with a 0.040 recessed crown. The action screws were torqued to 60 in.-lbs. per the Oryx directions prior to this session.

With the exception of the last two groups, I didn’t allow the barrel temperature to exceed 130 degrees, measured on temperature strips affixed to the barrels of both rifles. I made the exception because I had to shoot the last 8 shots of the last load more quickly than normal to get the load finished before a cease fire was going to be called. Fortunately, the RO gave me a bit of leeway and held up on calling the cease fire until I got the last few shots down range. The barrel temperature was over 140 when I got the final shot down range. With outside temperatures hovering around 70 to 80 degrees F, the 12 FV 6.5mm Creedmoor’s barrel temperature rises from about 85 to 130 degrees with just 10 shots and at over 120 degrees, the POI drops about 0.2 inches lower than when the barrel is cooler.

The load description field shows the powder and charge, the O.A.L., the trim length, and the bullet exit time from the 26-inch barrel.

# Grps.	Load Description	Bullet	Weight	Velocity	Average	Median	St Dev	1	2	3	4
4	IMR4350 41.3 gr 2.850 1.905 wf 1.361 * 71/71 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra 130 TMK #7430	130	2720	0.345	0.336	0.055	0.299	0.300	0.372	0.410
4	IMR4350 41.3 gr 2.831 1.902 wf 1.361 * 72/73 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra 130 TGK #4330	130	2721	0.392	0.398	0.060	0.314	0.385	0.410	0.457
4	H4350 41.4 gr 2.837 1.899 wf 1.361 * 73/76 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra 142 SMK #1742	142	2683	0.337	0.314	0.063	0.291	0.308	0.320	0.430
4	H4350 41.4 gr 2.313 1.896 wf 1.361 * 74/79 deg. F. 60 in.-lbs. Oryx CCI BR-4	Hornady ELD-M #26177	130	2721	0.357	0.361	0.033	0.313	0.355	0.367	0.392
16					0.358	0.346	0.059

Today’s session was somewhat sloppy. Somehow, I just didn’t seem to ever get into a groove and had trouble all session with getting comfortable with my set up. There were only two groups (12.5%) that were under 0.3 inches, when I have averaged 23.0% for all the groups shot to date. Also, there were 4 groups (25.0%) over 0.4 inches, more than the 21.6% average to date.

I thought that I was doing OK but when I finished the second load, I could see that I wasn’t shooting as tight groups as I normally do. The TGK hunting bullets usually shoot better than what today’s results show and have averaged 0.347 prior to today’s session.

Part of the impact on the TGK load was caused when the session was interrupted in the middle of the TGK load when the contract mowers arrived to cut the grass on the range. The last two groups of the second load showed the impact of the delay of about 45 minutes while we had to wait for them to finish cutting.
That’s no excuse because I should be able to get back in the groove immediately and not mess up two groups in a row. It just shows how hard it can be some days to keep my concentration. As I get older, it seems to be more difficult to keep my concentration sharp for the two to three hours that I am at the range. I guess at 76, I should just be thankful for being able to shoot at all, but I still want to perform well regardless of how old I get.

The last load was rushed because time was running out and I wanted to finish the last load before the next cease fire and I had almost two groups to go. I let the barrel heat up past what I consider to be a reasonable temperature. I just kept shooting so I could finish in time.

Even then, the last load wasn’t too far off the overall average for 5-round groups of 0.353, but today’s results moved the average up to 0.354. I’ve gotten spoiled by having the average continually drop after every session. Today’s was the first net loss in a long while. It may be that I am now at the point where the average will begin to stabilize.

It might be that you have already had the best groups the rifle is capable of.

charlie b,

You might be right, but I have only 1800 rounds down the tube on this 12 FV rifle and none were even close to Pmax.

A lot of people claim that the 6.5mm is a barrel burner and predict a 2,000 round barrel life. If so, this 12 FV could be close to its accuracy expectancy.
But my experience doesn't support those predictions.
I have over 4000 rounds through my other 26-inch 6.5mm Creedmoor barrel (12 LRP) and it is shooting as accurately as it ever has.
That was the rifle with the initial pressure issues caused by a tight chamber so it was experiencing high pressure even with relatively light loads.
I am hoping to get at least that many rounds through the 26-inch Savage barrel on the 12 FV.

Savage only uses only one type of barrel steel for all their barrels so the difference in the cost difference between the 12 FV ($320) and the 12 LRP ($1,095) is not in the 26-inch barrel but in the 12 LRP's HS Precision stock, detachable mag bottom metal, and the other aspects of the 12 LRP rifle's make up.

So we'll see if it was me during this session more than the rifle. Based upon my previous shooter induced variations, I would suspect the nut behind the trigger more than barrel wear.

Quote:

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Originally Posted by CFJunkie

So we'll see if it was me during this session more than the rifle. Based upon my previous shooter induced variations, I would suspect the nut behind the trigger more than barrel wear.

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LOL

I wasn't really referring to barrel wear as much as I was the barrel/action accuracy capability. At some point you just won't get better groups (except for the odd lining up of the stars that will give you a 0.1" group just due to statistical variations).

Now I get your drift and I completely agree with you. At some point it gets as good as it will ever get and stabilizes. That's the limit of rifle and shooter and it won't get any better on average. Of course, those statistical variations can appear but in my experience that happens about 0.1 to 0.2% of the time. A better shooter can do better but I probably won't.

The 'test' to see if it is the shooter is to do the same drill with another rifle. If the other rifle shoots smaller groups then the shooter is capable. :)

I only mentioned this because when you get below 1/2MOA it is the point where most rifles won't do any better (some won't get to that point). Heck, custom bench rest competition rifles used to win with .25" groups.

Your suggestion is a good one and makes a lot of sense.
Since I measure and record every group I shoot with just about any rifle, doing those comparisons is pretty easy.

Since January, I have been shooting 4 rifles.
I recognize that my emphasis has been on the two new 12 FV rifles since I got them in March mand the number of groups recorded is still small enough (under 300) to make any improvements very visible on the overall average.
The improvements have been small for the other two rifles but they have a lot of groups recorded and it takes a enormous change in a few sessions to make any change in overall average.
One of my Savage .308's average improved 1.9% and the other .308's average improved by only 0.5%.

But for the 12 FV rifles, since I was concentrating on the bullets and powders that shot best, the improvements were being skewed by concentrating on shooting the powders and bullets that worked best.
The most improvement has been with the 12 FV .223 with the new Oryx stock but that was influenced by shooting the 77 grain bullets that shoot much better than just about anything I have tried. Changing the stock and shooting the 77 grain bullets made the most difference and improved the overall average from 0.412 in June with old stock to 0.304 (26.2%) by the end of August with the new Oryx chassis and the 77 grain bullets.

The 12 FV 6.5mm averaged 0.342 with the factory stock through May and has averaged 0.277 with the Oryx stock from early June through the end of August. That is a 19% improvement, mostly attributed to the change to the Oryx chassis (since I hadn't also discovered a magic bullet to further improve the average like finding the 77 grain Sierras for the .223).
This last session, with the 12 FV 6.5mm new Oryx chassis, I averaged 0.358 using the same bullets that had averaged 0.267 since the Oryx chassis was introduced through August. The bullets I shot during the last session were among the better performing bullets.
I have to conclude that it wasn't the bullets that caused the drop in performance.

I have to just accept that I had a bad day at the range and resolve to just do better at the next session.

WELL FORK, thought I had found a stock for a left handed shooter, it seams that ORYX isn't interested to supplying left hand shooters with their products.
maybe "plan "B" ??

The following are the results shot with the 12 FV 6.5mm Creedmoor in the Oryx stock in Northern Virginia Saturday morning, September 21^st at 100 yards. Temperatures were from 57 to 73 degrees with winds from 1 to 3 mph. Altitude of the range is 250 feet above sea level.

I decided to test the performance of IMR4451 powder with a variety of bullets that hadn’t been shot with the Oryx stock and that powder to add to the basis of comparison between IMR4451 powder and H4350 powder as well as between the Oryx chassis and Factory stock, both with the NightForce scope. All the groups were shot with a NightForce 8-32x56mm Benchrest scope. All rounds were shot using Lapua brass and CCI BR-4 primers. All loads were set up to match the 12^th reflection time of 1.361 msec. which should be the ‘sweet spot’ for the 26-inch barrel with a 0.040 recessed crown. The action screws were torqued to 60 in.-lbs. per the Oryx directions prior to this session.

I loaded all the loads out to 0.020 jump based upon the latest erosion figures for the chamber.
The 147 gr ELD-M and the 140 ELD-M were loaded out at 2.929 and 2.899 respectively and wouldn’t feed out of the AI Industries AICS magazine. I had to load them one at a time.

The load description field shows the powder and charge, the O.A.L., the trim length, and the bullet exit time from the 26-inch barrel.

# Grps.	Load Description	Bullet	Weight	Velocity	Average	Median	St Dev	1	2	3	4
3	IMR4451 39.1 gr 2.842 1.903 wf 1.361 * 57/58 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra SMK #1742	142	2664	0.296	0.295	0.030	0.280	0.263	0.310	0.329
4	IMR4451 39.4 gr 2.929 1.900 wf 1.361 * 67/68 deg. F. 60 in.-lbs. Oryx CCI BR-4	Hornady ELD-M #26333	147	2651	0.304	0..298	0.069	0.229	0.282	0.313	0.393
4	IMR4451 39.4 gr 2.899 1.898 wf 1.361 * 71/70 deg. F. 60 in.-lbs. Oryx CCI BR-4	Hornady ELD-M #26331	140	2674	0.278	0.288	0.039	0.223	0.284	0.291	0.313
4	IMR4451 39.4 gr 2.869 1.894 wf 1.361 * 76/73 deg. F. 60 in.-lbs. Oryx CCI BR-4	Hornady ELD-M #26177	130	2706	0.364	0.384	0.109	0.221	0.339	0.429	0.466
16					0.310	0.301	0.070

The results were pretty good until the last load with the 130 ELD-M bullets. Admittedly, I had to rush the last three groups to get finished in time before a cease fire or wait another 30 minutes before I could shoot the last two groups. I’m not sure the rushing or the barrel heating cause the increase in the last two groups, but they grew and messed up the load.
Actually, the results weren’t all that bad overall.

Three of the loads the 4^th best, 8^th best and 12^th best loads out of the 87 different loads shot so far. The worst load was the 130 ELD-M load and it managed to make the 58^th load.

Based upon this data, I was able to compare the performance of 6 different bullets shot in both the factory stock and the Oryx chassis with IMR4451powder with the NightForce scope. The Oryx chassis provided a 7.4% improvement over the factory stock.

I was also able to compare the same bullets shot with IMR4451 powder on the factory stock (all shot at 35 in.-lbs. of torque) to compare the Sightron 36X42mm fixed power scope and the NightForce 8-32x56mm Benchrest scope and found the NightForce scope achieved an 8.4% improvement even though it had 4 power less magnification. I think the difference was the result of the brighter image gathering capability of the 56mm front optic on a 30mm tube versus the 42mm front optic on a 1-inch tube when shooting in the early morning hours in dim light.

The following are the results shot with the 12 FV 6.5mm Creedmoor in the Oryx stock in Northern Virginia Wednesday morning, September 25^st at 100 yards. Temperatures were from 59 to 69 degrees with winds from 1 to 3 mph. Altitude of the range is 250 feet above sea level.

I also was shooting my Savage 12 FV .223, interchanging the two rifles to let the barrels cool. The .223 heats up more slowly so I managed to shoot more groups and loads with the .223 than with the 6.5mm Creedmoor. The .223 results are reported on a different thread on this same 110 Rifle forum.

I decided to test the performance of H4350 with a variety of bullets that hadn’t been shot with the Oryx stock and that powder to add to the basis of comparison between IMR4451 powder and H4350 powder as well as between the Oryx chassis and Factory stock, both with the NightForce scope. All the groups were shot with a NightForce 8-32x56mm Benchrest scope. All rounds were shot using Lapua brass and CCI BR-4 primers. All loads were set up to match the 12^th reflection time of 1.361 msec. which should be the ‘sweet spot’ for the 26-inch barrel with a 0.040 recessed crown. The action screws were torqued to 60 in.-lbs. per the Oryx directions prior to this session.

I loaded all the loads out to 0.020 jump based upon the latest erosion figures for the chamber.

The load description field shows the powder and charge, the O.A.L., the trim length, and the bullet exit time from the 26-inch barrel.

# Grps.	Load Description	Bullet	Weight	Velocity	Average	Median	St Dev	1	2	3	4
4	H4350 41.5 gr 2.880 1.910 wf 1.361 * 59/59 deg. F. 60 in.-lbs. Oryx CCI BR-4	Hornady ELD-M #26331	140	2690	0.286	0.282	0.040	0.241	0.271	0.293	0.337
4	H4350 41.5 gr 2.876 1.910 wf 1.361 * 64/65 deg. F. 60 in.-lbs. Oryx CCI BR-4	Berger VLD M #26401	140	2691	0.323	0.324	0.073	0.235	0.302	0.345	0.408
4	H4350 41.5 gr 2.860 1.909 wf 1.361 * 70/69 deg. F. 60 in.-lbs. Oryx CCI BR-4	Sierra SMK #1742	142	2685	0.303	0.314	0.049	0.234	0.308	0.320	0.350
12					0.304	0.305	0.053

The results from this session were interesting in that the Berger VLD Match bullets managed the best group size average for the H4350 load yet achieved for that bullet. Actually. it earned a rank of #22 out of 90 loads shot with this rifle. The next best load with this bullet using IMR4451 powder ranked #65 in comparison. I think I finally have found where to seat this bullet to achieve acceptable accuracy.

The average of all 140 ELD-M loads with H4350 is now 0.306, so this load achieved the #5 position on the rank of all loads with this rifle. The best load with this bullet ranks #4 using IMR4451 powder.

The average of all 142 SMK bullets with H4350 powder is now 0.327 and this load achieved a overall rank of #12 in the rank of all loads with this rifle. The best load with this bullet ranks #8 using IMR4451 powder.

The average of all bullet and powder combinations for this rifle is now 0.350 so this session managed to lower the overall average slightly, even though it didn’t seem especially spectacular, other than with the 14 ELD-M bullet load.

Thought that I should provide an update for this 12 FV CM in the Oryx chassis after several months of lay off after the death of my wife of 54 great years.
I sort of shriveled up a bit for a while but finally decided to try to get back to shooting to rekindle my passion for shooting small groups.
I loaded for the 12 FV 6.5mm CM in late January and again in early February.

I finally got back to the range in late January and I figured I would update the results for this rifle (with the Oryx stock replacement).
If you want to compare the results for the 12 FV 6.5mm CM with the factory stock, they are posted in a thread in the Ammunition and Reloading Board.

I shot both sessions using H4350 powder (temperature insensitive for the cold mornings) with CCI BR4 primers.
i tried a different format that isn't as long winded and doesn't have so many problems with trying to keep the text columns in line.
I hope it is not too bothersome.

The impact of the long layoff can be seen in the Jan 24th results.
Attachment 6968
But after shooting my 12 FV .223 in an Oryx stock a few times between these two sessions, I think I got my consistency back during the February 8th session.
Attachment 6969
The overall average for this rifle with 5-round groups dropped from 0.345 in October for 361 groups to 0.342 for 401 groups in November.
The 5-round group average remained at 0.342 for for 431 groups after the February session, primarily on the basis of the Feb 8 session producing one of the better sessions with this rifle and balancing out the less spectacular session in late January.

This will be the last entry for a while. They just closed our range because of the corona virus.
Even though it is an outdoor range with plenty of space for separation, a majority of RSOs who are mostly geezers like me, didn't want to be exposed.
I did my last RSO session on the 9th and my last range visit on the 16th, the day before they closed the range.

Here is my most recent data.
You'll note that the dates for the first three loads were on the 9th and the last load was shot on the 16th. The range was too busy on the 9th for me to find the time to shoot all 4 loads and still monitor the range. I arrived early to shoot the first two loads before I took over and shot the last load when most of the shooters departed to beat the traffic. Winds varied from 5 to 7 mph with some gusting and were the worst for the 2nd load just before I took over the range. I might have been rushing a bit to finish up - that usually messes up my averages.

On the 16th the winds were slightly different. The winds were a bit calmer - around 5 mph.

Attachment 7004