First results with new 12 FV .223

[CFJunkie]

I'm glad you liked the records of my loads with the .223. I thought serous shooters would get some value from posting them.

As for primer pocket wear, I had primer pocket wear problems similar to yours with my 6.5mm CM when it had a tight chamber (from the factory).
I got only 4 reloads with new Norma large primer brass regardless of what loads I used, even loads down at minimum pressure around 37,000 psi.
Savage bored the chamber out a few thousandths and now I get over 20 reloads with Lapua small primer brass.
Fortunately, the 12 LRP is now just as accurate with the bored chamber as it was with the tight chamber.
When I was researching the cause or worn primer pockets, the Hornady staff told me that precision barrels often have tight chambers to increase accuracy, but the tight chambers increase pressure conditions.
Personally, I think I just got a chamber that was cut with a reamer that was about worn out when they got to my barrel.
From my experience with the 12 LRP, high pressure conditions really do a job on primer pockets.

Other than that one rifle, I have had much better luck with numbers of reloads than you have across the board.
I have been using Lapua brass for at least 8 years and get over 20 reloads per lot with all my calibers - .223, .22-250, 6.5mm CM, and .308. My last lot of 6.5mm being used with my 6.5mm CM is on its 11 resize - 12 firings - and the primer pockets are still tight. That's over 1,000 rounds resized with the original brass. With that brass lot, I have never loaded any loads above 58,000 psi against a 63,000 psi Pmax.

I admit that because I am loading for exit time, I usually keep the loads well below Pmax, with the exception of my Les Baer Super Varmint .223 that has a 416R 18-inch barrel. The reflection times get loads very close to Pmax with some powders and over Pmax with others like Varget and H4895.

The 12 FV .223 I have been shooting for this thread has a 26-inch barrel and it stays well below Pmax unless I try to use the 10 reflection (1.134 msec.) with the heavy bullets and the .308 powders, especially the 77 grain bullets. That's why the load I used in post #19 with the 12 FV .223 is at 1.360 msec. reflection time - 1.360 msec. is the 12th reflection.

I don't seem to need to push the velocity and pressure to get accuracy.
If anything, I get better results with moderate velocities and pressures.
The sole exception is the Les Baer .223. I seems to retain its accuracy with the higher velocities and pressures, but at the expense of brass.
But ARs tend to mess up brass much more than bolt actions so I use mostly Federal brass with the Les Baer.

[CFJunkie]

Come to think of it, Remington 7 1/2 Benchrest primers are a bit smaller in diameter than the CCI BR primers I have been using for the 12 FV and for my Les Baer.
The difference isn't great, but it doesn't take much to get a loose primer.
I always used Rem 7 1/2 primers with my original CZ 527 Varmint .223, but I didn't shoot heavy bullets with the CZ 527 Varmint until recently, so the powders were suited to lighter bullets.
However, the Rem primers didn't get loose in Lapua brass so I don't think it was just the primers.
I still think pressure has something to do with loosening primers.

I loaded a batch of Rem 7 1/2 primers with some 69 gr and 77 gr SMKs and TMKs and see if it makes any difference, either in accuracy or in primer pockets.
If the primers are loose, there should be some indications, like cavitating firing pin strikes as the primer moves back against the bolt.

I'll let you all know after I get to the range with the 12 FV .223 to try out the new loads.

[charlie b]

Thanks for the prompt reply and the offer to test the primers. I know that Rem primers are known for being a bit on the 'soft' side so that may contribute. I was planning on changing to the CCI BR primers anyway. I use the large ones in my other rifles.

I thought about the case expansion a bit. Then it hit me that my previous .223 was a Contender, with a fully supported barrel, so it might never have seen loose pockets.

Just curious, what equipment are you using to measure things like exit time and determining shock wave reflection? As far as I understand it you'd need to know rate of change of acceleration down the barrel. Or is the shock a calculated number based on barrel length and muzzle velocity?

[CFJunkie]

The speed of the reflection in the steel is the starting point.
Identifying the steel in your barrel is the first step.

Regular barrel steel reflects at 18, 916 fps.
3% carbon steel reflects at 19,107 fps. Savage barrels fit this category.
4140 and 4150 stainless steel reflects at 19,979 fps.
416R steel reflects at 20,014 fps.
The Materials Handbook lists 'Stainless Steel' with a generic speed of 20,000 (probably to cover everything from 4140 and 4150 and 416R stainless).

Then you have to know the length of your barrel from bolt face to the muzzle (consider the recess of the crown as not being part of the barrel steel.)
With the length of the barrel and the reflection time of the steel, you can calculate the time to go from the chamber to the muzzle.
Then you double it to get back from the muzzle to the chamber.
Do that about 10, 12 or 14 times and you get the exit time goals for your rifle.
You want the exit time to be on an even reflection because that is when the shock wave is back at the chamber when the bullet is leaving the muzzle.

The theory is that the less shock at the muzzle give you less vibration as the bullet leaves and also keeps the crown the tightest as the bullet is leaving.

QuickLOAD actually calculates the exit time and accounts for the acceleration of the bullet based upon the powder charge as well as considering the, barrel length, seating depth and trim length on the pressure when the bullet fires.

The choice of reflection time to match against exit time is up to you to figure out.


Even though QuickLOAD is a simulation, and many questions its validity based upon that, my seven rifles, accurate enough to use exit time for loading, produce results within 0.001% to 0.002% of the QuickLOAD calculated exit time. That variation can easily be caused by the mix of carbon in a particular barrel steel or poor barrel measurements on my part.

I built a spreadsheet to calculate reflection time based on the steel of my various barrels and their measured lengths.
You have to include the length of muzzle brakes, flash hiders and suppressors in the reflection time if they are attached to the barrel.
The problem with those appendages is identifying the metal they are made of and getting an accurate measurement of their mounted length and contribution to reflection time.

[charlie b]

Thanks for that. I kinda figured since actual measurements require some interesting (and expensive) instruments. Have not worked with them on firearms but have used them on explosives tests.

[hamiltonkiler]

I got a note from another shooter who told me that he shot 77 gr SMKs in his 1:9 twist .223 and had good results.
He claimed that the bullet shape overcame the stabilization problem.
I have had great results with 77 grain SMKs and TMKs in my 1:8 .223 but I have always read that a 1:9 twist wouldn't stabilize bullets over 73 gr bullets, so I never tried them in my two 1:9 twist rifles.

Always curious to try something I haven't tried yet, I loaded up 77 gr Sierra SMKs and TMKs with IMR4166 powder at the 12th reflection time (1.360 msec.) at 2540 fps in my 12 FV .223 and gave them a try.
The 10th reflection time (1.134 msec.) pushed the pressure over Pmax.

I was really surprised at the results.

# Grps -------- Load Description -------- --- Bullet --- Wgt. --- --Vel-- -- Avg. -- Median --St Dev-- ---1--- ---2--- ---3--- ---4---
-- 3 --- IMR4166 21.0 gr 2.384 1.758 --- SMK #9377 --77 ----- 2540 -- 0.515 -- 0.524 --- 0.045 -- 0.466 - 0.524 - 0.554
-------- wf 1.360 75/77 deg. F.
-- 4 ---IMR4166 20.9 gr 2.330 1.757 ---- TMK #7430 -- 77 ----- 2436 -- 0.280 -- 0.273 --- 0.053 -- 0.239 - 0.232 - 0.307 - 0.340
-------- wf 1.360 77/80 deg. F.
-- 7 --- Total ------------------------------------------------------------------ 0.380 -- 0.340 --- 0.134
-------- wf 1.360 77/80 deg F.

I have to say I was amazed by the performance of the TMKs compared to the SMKs.
So much for the concerns about stability problems with 77 grain bullets.
The SMKs averaged 0.270 better than the 70 grain Berger bullets that I had tried in earlier sessions but the TMKs shot
0.022 better than any bullets I had tried with the 12 FV .223 so far.
I don't know if the results are atypical but I suspect that the higher ballistic coefficient of the TMKs might have had something to do with aiding in stabilization and achieving these results.

The 77 TMKs also out perform the 77 SMKs in my 1:8 twist.
Actually, TMKs that are similar weights to SMKs in my .308s consistently out perform the SMKs as well as long as the O.A.L. is longer to account for the 0.070 longer tips and get the ogive in the same place wrt the chamber.

I have always been surprised that no one supplies factory ammo with TMKs.
Perhaps it is because the TMKs would have to be seated longer by at least 0.050 and that might cause problems for magazine limits on some rifles.
Factory ammo just can't adapt for individual rifle chamber depths like a reloader can.
They would have to seat back to account for the smallest magazine and, from my experience, that would limit any benefits of the TMK wrt accuracy.
AR type mags limit seating depth on my 1:8 Les Baer Super Varmint and have forced me to use a single round follower with TMKs to seat the TMKs out where they perform best.
Thankfully, Savage mags have plenty of space for seating out the TMKs to take advantage of the TMK's inherent accuracy.

https://uploads.tapatalk-cdn.com/20190624/c13631d2df271dc0805a170bc80d6867.jpg
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Good article here. I haven’t ever messed with the tmk. Here is my verified dope to 600yds with mk262 mod1


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[CFJunkie]

hamiltonkiler,

I stand corrected. Apparently Black Hills provides factory ammo with TMK bullets.

The TMK has a higher BC than the SMK so that should account for its flatter performance at 1000 yards.

But from your pictures, I notice that the Black Hills TMK loads are seated way back into the brass. It looks like the ogive is at the neck.
The TMK is a longer bullet than the SMK by 0.070 so the O.A.L. should be well out past the seating depth for the SMK.
The Sierra manual recommends the same O.A.L at 2.260 for both.
I asked Sierra and they admitted that they were influenced by the AR magazine limitations in recommending that O.A.L.

That means that the jump for the TMK would be about 0.050 longer than for the SMK seated at the same O.A.L.

I seat my SMKs at 2.280 to 2.290 with my 12 FV and the TMKs at 2.320 to 2.350. At those seating depths, the TMK really comes into its own.

[CFJunkie]

The following are the results with the Savage 12 FV 6.5mm Creedmoor shot in Northern Virginia on Thursday morning, June 24, at 100 yards. Temperatures from 73 to 81 degrees with winds from calm to 3 mph. Altitude of the range is 250 feet above sea level.

All rounds were shot using Lapua brass and Remington 7 ½ primers with an 36x42 fixed power Sightron scope with a target dot reticle. All bullets were loaded to achieve a 1.360 msec. exit time which should be the sweet spot for a 26-inch 3% carbon steel barrel with a 0.040-inch recessed crown. The action screws were torqued to 35 in.-lbs. prior to this session.

I used the Remington Benchrest primers in place of the CCI BR-4 Benchrest primers that I normally shoot because I promised poster 'charlieb' to shoot them to check their performance against the BR-4 primers. The sample is small compared to the BR-4 data but the results are promising. I will try the Remington 7 1/2 primers again at another session.

This morning I shot Sierra SMK and TMK bullets in 69 and 77 grain weights to see how they compared on the same day, assuming that I could shoot consistently enough over about 3 hours to provide a reasonable comparison.

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
IMR4166 21.4 gr 2.292 1.760 wf 1.360 * 74/74 deg. F. 35 in.-lbs.
Sierra SMK #1380
69
2585
0.280
0.281
0.0.062
0.202
0.280
0.282
0.355


3
IMR4166 21.1 gr 2.320 1.759 wf 1.360 * 80/79 deg. F. 35 in-lbs.
Sierra TMK #7169
69
2574
0.265
0.270
0.034
0.229
0..270
0..297



4
IMR4166 21.0 gr 2.282 1.757 wf 1.360 * 80/86 deg. F. 35 in.-lbs.
Sierra SMK #9377
77
2540
0..306
0.329
0.054
0.225
0.377
0.331
0.340


4
IMR4166 20.9 gr 2.330 1.755 wf 1.360 * 83/81 deg, F.
Sierra TMK #7177
77
2536
0.260
0.256
0.029
0.232
0.244
0.267
0.298


15




0.279
0.280
0.046


























Today’s spectacular overall average of .279 was incredible compared to the overall average of 0.378 for all 66 groups shot with this rifle.
I could attribute the performance to the light winds, but I also shot my 6.5mm Creedmoor right at its overall average, so I think it was the bullets and the seating depth matched to this rifle.

[CFJunkie]

Correction to post #28
The results posted are obviously for the 12 FV .223.
I have made so many posts for the 12 6.5mm Creedmoor that I automatically typed that in the first line.
All the other information is correct.
Sorry for the confusion.

[hamiltonkiler]

The following are the results with the Savage 12 FV 6.5mm Creedmoor shot in Northern Virginia on Thursday morning, June 24, at 100 yards. Temperatures from 73 to 81 degrees with winds from calm to 3 mph. Altitude of the range is 250 feet above sea level.

All rounds were shot using Lapua brass and Remington 7 ½ primers with an 36x42 fixed power Sightron scope with a target dot reticle. All bullets were loaded to achieve a 1.360 msec. exit time which should be the sweet spot for a 26-inch 3% carbon steel barrel with a 0.040-inch recessed crown. The action screws were torqued to 35 in.-lbs. prior to this session.

I used the Remington Benchrest primers in place of the CCI BR-4 Benchrest primers that I normally shoot because I promised poster 'charlieb' to shoot them to check their performance against the BR-4 primers. The sample is small compared to the BR-4 data but the results are promising. I will try the Remington 7 1/2 primers again at another session.

This morning I shot Sierra SMK and TMK bullets in 69 and 77 grain weights to see how they compared on the same day, assuming that I could shoot consistently enough over about 3 hours to provide a reasonable comparison.

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
IMR4166 21.4 gr 2.292 1.760 wf 1.360 * 74/74 deg. F. 35 in.-lbs.
Sierra SMK #1380
69
2585
0.280
0.281
0.0.062
0.202
0.280
0.282
0.355


3
IMR4166 21.1 gr 2.320 1.759 wf 1.360 * 80/79 deg. F. 35 in-lbs.
Sierra TMK #7169
69
2574
0.265
0.270
0.034
0.229
0..270
0..297



4
IMR4166 21.0 gr 2.282 1.757 wf 1.360 * 80/86 deg. F. 35 in.-lbs.
Sierra SMK #9377
77
2540
0..306
0.329
0.054
0.225
0.377
0.331
0.340


4
IMR4166 20.9 gr 2.330 1.755 wf 1.360 * 83/81 deg, F.
Sierra TMK #7177
77
2536
0.260
0.256
0.029
0.232
0.244
0.267
0.298


15




0.279
0.280
0.046


























Today’s spectacular overall average of .279 was incredible compared to the overall average of 0.378 for all 66 groups shot with this rifle.
I could attribute the performance to the light winds, but I also shot my 6.5mm Creedmoor right at its overall average, so I think it was the bullets and the seating depth matched to this rifle.

I am not familiar with load data. Sorry for the ignorance. When did you see pressure signs? What was the discussion about loose primers? I wonder if that’s why the mil spec ammo has sealed primers? I wonder what your ballistics or dope is down range with the loads your shooting at the velocities, as the 100yd groups are very impressive.
Cheers


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[charlie b]

Thanks for trying the rem primers. I am going to measure some brass and see if the base area is expanded. I suspect they are and I will need to get some more brass. So, will get some Lapua and see how they do. I may keep some of the worn brass and see if it can be sized back to a useful dimension.l

I like the groups. So why did you settle on 4166 for a powder? I have only tried H322, WW748 and Varget this time around. Used the WW powder years ago with lighter bullets and it did well back then.

[CFJunkie]

hamiltonkiler,

charlie b asked about loose primer pockets in post #20. I responded to his concerns in post #21 and switched to Remington 7 1/2 Benchrest primers to help him out with a test.
I wasn't seeing pressure signs with the 12 FV .223.

In general, military brass is usually intended for one use and not for reloading so primer pocket wear is not the issue for the military.
However, they use harder primers because they shoot rounds in semi-autos and they protect against slam-fires.
I suspect that the primers in military rounds may be sealed to protect the rounds from bad weather conditions and from long storage periods in widely varying temperatures.

[CFJunkie]

charlie b,

No problem. I have thousands of Rem 7 1/2 Benchrest primers lying around. I used to shoot them exclusively in my CZ 527 Varmint .223 bolt action until I got my Les Baer Super Varmint .223 and decided to go with the harder CCI 400 and CCI BR-4 primers with its AR action to eliminate the possibility of slam fires. It was nice to see they preform as well in my new bolt action .223 as they did before.

As for primer pockets, I would suspect that the primer pocket has worn because it was forced back out of the pocket by the high pressure of the charge multiple times. I have found that once the primer pockets get loose, there is no way to make them tight again so the brass goes in the recycle pile.
The only way to make the primer pockets last as long as possible is to reduce the pressure of the loads. I find if I keep the charge around 15% lower than Pmax, I have no problems with primer pockets. But when I have to get close to Pmax, the primer pockets wear out quicker.

A tight chamber can make watching powder charges incidental because a tight chamber increases pressure as well.
I had a 6.5mm Creedmoor rifle that flattened primers even with 37,000 psi loads which were at the low end of the powder table.
I suspect they used a worn reamer at the end of its use when the reamed the chamber at the factory.
The chamber was bored out 0.002 thousandths and the problem went away.
I now shoot that particular rifle at 10% of Pmax with no pressure signs and no primer pocket issues.

I am using IMR4166 Enduron powder because it is a anti carbon-fouling powder and with the amount of shooting I do, copper fouling is an issue.

For heavier bullets, over 60 grains, I have found that 'what I call my .308 powders' - Varget, H4895, N140, & IMR4166 - produce the best accuracy.
For lighter bullets, I have had the best results with H335, H322, N133, and CFE223 with the bullets under 60 grains in all of my .223s. I was using N133 in the 12 FV .223 because it was handy and I had more of it than any other light bullet powder.
CFE223 is the only 'light bullet powder' that provides top accuracy with the heavier bullets too.

[CFJunkie]

The following are the results with the Savage 12 .233 shot in Northern Virginia on Friday morning, June 28 at 100 yards. Temperatures on Monday were from 76 to 82 degrees with winds from calm to 3 mph. Altitude of the range is 250 feet above sea level.

At last week’s Thursday session, I tested the 12 FV .223 with 69 and 77 grain bullets and the results were so impressive, I decided to extend the test to see if I could make the results more statistically significant.

All rounds were shot using Lapua brass and Remington 7 ½ small rifle primers with 36X fixed power Sightron scope with a target dot reticle. All bullets were loaded to achieve a 1.360 msec. exit time which should be the sweet spot for a 26-inch 3% carbon steel barrel with a 0.040-inch recessed crown. The action screws were torqued to 35 in.-lbs. prior to this session.

For this session, I loaded IMR4166 Enduron powder and I planned the seating depths so all the different bullets would achieve the same jump to the rifling – 0.020 – and then adjusted the seating depth by less than 0.005 thousandths to achieve the 1.360 exit 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
IMR4166 21.4 gr 2.290 1.758 wf 1.360 * 77/76 deg. F. 35 in.-lbs.
Sierra SMK #1380
69
2585
0.324
0.292
0.098
0.246
0.292
0.434



4
IMR4166 21.2 gr 2.336 1.756 wf 1.360 * 80/80 deg. F. 35 in-lbs.
Sierra TMK #7169
69
2578
0.272
0.276
0.015
0.250
0.274
0.277
0.286


4
IMR4166 21.1 gr 2.298 1.754 wf 1.360 * 83/82 deg. F. 35 in.-lbs.
Sierra SMK #9377
77
2543
0.254
0.258
0.021
0.228
0.245
0.270
0.272


4
IMR4166 21.0 gr 2.344 1.752 wf 1.360 * 86/85 deg, F.
Sierra TMK #7177
77
2540
0.299
0.305
0.045
0.244
0.281
0.329
0.343


15




0.285
0.274
0.052


























Today’s session coupled with Monday’s session shown in post #28 matches these results pretty closely (average for 77 SMK s was 0.306 and the average of the 77 TMKs was 0.260.)

The session reported in post #19 using CCI BR-4 primers didn’t show results quite as good for the 77 grain SMKs (avg of 0.515) but did show a very comparable result for the 77 grain TMKs (average of 0.280.)

The combined totals for the 77 grain rounds are as follows:
Bullet Avg.-- Median St Dev -- # Grps.
SMK - 0.344 - 0.327 0.118 ------11
TMK - 0.280 - .0274 0.043 ------12

[charlie b]

Thanks for all that info. It is really helpful and may get me to switch powder for the .223. I like the 77gn SMKs for it so your info is ideal. I may also reduce my loads a bit to see if that helps. Right now I need to go buy some brass :)

My .308 seems to be doing ok with Re15. A bit less than MOA. Varget gets me less than MOA at all the loads I tried. It did not like reduced loads at all. I also tried Blc2 and IMR4895. The Blc2 seemed ok but the IMR4895 was not.

[CFJunkie]

charlie b,

I have two Savage .308s, both model 10s, but one likes bullets in the 175 to 200 grain range and the other likes bullets in the 150 to 168 grain range.
Both have 24-inch barrels but one has a muzzle brake, so I have to allow for the added reflection time when I am loading.
Their average 5-round group sizes are within 0.6% of each other at around 0.452 so there is little difference other than their bullet weight preferences.

They both really shoot the Sierra Tipped Match Kings better than any other bullets.
One shoots the 175 gr & 195 gr TMK bullets best and 168 gr TMK bullets almost as well.
This rifle has TMK bullets with all the powders in the top 12 places on this rifle Powder-Bullet summary table.
The other shoots the 155 gr and 168 gr TMK bullets best and 175 gr TMKs almost as well.
This rifle has TMK bullets with multiple powders in the top 11 places on this rifles Powder-Bullet summary table.

Both rifles provide the best accuracy with H4895 and IMR4166 Enduron powders.
I have tried IMR4064, N140 & RL-15 powders as well but I get the best accuracy with H4895 and IMR4166, just with different bullets.
Both H4895 and IMR4166 Enduron powders are extreme powders and are temperature insensitive.
IMR4064, RL-15, N140, and IMR4895 are very temperature sensitive, just the opposite of the two most accurate powders.
The temperature sensitive powders change from 1.2 to 1.5 fps per degree F. so you really have to know what temperatures you are loading for from session to session and from the start of a session to the end of session.
Here in Northern VA, temperature can change more than 15 degrees from 8 AM to Noon so temperature is a concern. I presume that temperature changes can be even more severe in New Mexico.

[charlie b]

Thanks for that help. Mine is the 12BVSS so longer barrel and no brake. And it seems to prefer 155s but it just may be that I have not found the right combination. I will try the 4166 especially since it may work better than the Varget in the .223 as well.

Yep, we can get temp swings of 30 deg during a morning shooting session but 20 deg is more common. Higher heat and direct sunlight is another problem. At 4500ft it keeps the barrel toasty hot. I am careful to not let a cartridge sit in the barrel.

Then during the winter I will shoot when it is in the 30's.

[CFJunkie]

charlie b,

Varget powder has the smallest variation in fps of all the extreme powders in .308s - only 4 fps over the range of 0 to 125 deg. F.
H4895 is seoncd with 8 fps.
In my experience, I think most powders seem to work better in some rifles than others and with particular bullet weights, but it might simply be that the seating depth and powder charge (velocity & pressure) needs to be adjusted to get the best out of any individual powder.

I have shot both in .308s, but recently I have gotten better results with H4895 and more recently with IMR4166, but I have to admit, I have recently really improved my shooting technique and reloading technique also so I can't make any conclusions about the powder performance in my .308s.

When I finally decided, several years ago, that it was the 'nut behind the trigger' that was causing most of the spread in my group sizes, I made astonishing improvements in my accuracy simply by fixing my technique.
Then I started with the 'barrel reflection time' tuning for 'bullet exit time' and improved my accuracy by an additional 15 to 20%.
After all the changes, my average group sizes are about half the size they were 6 years ago.

I am now a firm believer that if I didn't eliminate most of my 'shooter induced variations' and 'reloader induced variations' I would have never been able to measure the improvement I gained from 'barrel reflection time' tuning. My induced variations would have simply masked any improvements that were occurring.
I still have lapses, as looking at my data clearly documents, but the lapses are relatively rare and once I notice them, I can quickly go back to basics and recover.

[thaifighter]

We're getting similar results out of a 12fv. Once fired Rem brass and 25.4gr varget and cci bench rest primer with 69 gr SMK gets one ragged hole groups at 100. COAL 2.235". My wife's hitting 8" gongs at 500 yards with boring regularity.

[CFJunkie]

thaifighter,

Seems like you're loading those 69 grain SMKs really short unless that was a typo in your COAL data.
I have had best results at from 2.280 to 2.300 with the 69 SMKs.
I recommend that you also try some 69 TMKs loaded out at 2.340 to 2.350. The TMKs shoot even better than the SMKs and seem to be even more consistent.

You might even try some 77 SMK and TMKs as well. I didn't think they would be accurate in a 1:9 twist but boy was I wrong.
They shot better than the bullet weights that a 1:9 is supposed to shoot accurately.
I guess I learned a lesson.

Good to see you're getting great results from your 12 FV .223 as well.
The 12 FV series is a tremendous bargain and I know 3 people at our range who have had great results with their 12 FVs as well, so it seems like the norm.
Cabela's specified just the right stuff for Savage to put in their 'built for them' package.