First results with new 12 FV .223

[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 b

etter 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.

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.

[thaifighter]

I appreciate the info, I will play with the COAL and see if I can improve on what we're seeing. I agree that the FV's were a HUGE value. I am still kicking myself for cancelling an order for a .308 due to it being out of stock and not wanting to wait.

I'll look into the TMK. I am also looking at the 60gr Partition to get my wife prepped for next year's deer season. She's been shooting a Howa in 6.5, but she loves the 12 so much, she's asked me to get a load setup for it.

[charlie b]

......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.

Yep, I am in this category, ie, I still need more work to improve groups. My personal ability at the present is around .5MOA. I am working on that.

Curious, with your current shooting ability have you compared a 'book standard' load to one of your tuned loads? Maybe factory Federal Gold Medal Match ammo (or Black Hills)?

[CFJunkie]

With the 12 FV .223, I have shot factory 69 SMKs and even figured out an approximate exit time based on the claimed muzzle velocity.
I shot 5 groups

to an average of 0.431with 69 gr SMK bullets in Federal Premium Gold Medal Match factory ammo with an average O.A.L. of 2.245 with what I suspect is an exit time of from 1.157 to 1.165 msec.

That exit time would be 0.023 to 0.031 msec. off the reflection time for the 12 FV putting the reflection slightly more than 20% down the barrel from the chamber.

My average with equivalent powder with 69 SMK bullets is 0.298 for 20 groups at an exit time of 1.133 to 1.134 msec. (which is right at the chamber on the 10th reflection) with most of the loads shot with a 2.280 to 2.290 O.A.L.
That is a pretty small statistical sample of groups with the factory and a very good statistical sample for the hand loads.

The average group size difference between the FPGMM and my hand loads is 0.153 or 33.9% smaller than the factory group average.
That percentage is just about the same percentage that I found with my 12 LRP 6.5mm Creedmoor with Hornady 140 gr ELD-M and my hand loads with the same bullets.

Based upon my experience, an exit time of 0.023 to 0.031 msec. off the chamber exit time is worth about 0.015 to 0.025 in group size average. If my estimate of the factory exit time is off by 0.030 more, the difference could be up in the 0.060 range. But that is only 1/3rd of the difference in average between the hand loads and factory average.
I suspect the remainder of the difference can be attributed to the shorter bullet jump of 0.040 for the factory round.
There might be a bit of a difference due to my reloading technique versus a production reloading machine, but there is no way to tell what that might be.
For all of my rifles, even the ones that I don't tune for exit time, my hand loads shoot better than factory universally.
I think some of that is caused by the factory practice of using O.A.L.s that is about 0.005 shot of SAMMI recommended O.A.L. so their rounds will fit just about any chamber made in that caliber.
I generally measure all my chambers and find loads that work best for that chamber length.

[charlie b]

Thanks for that info. It is not as bad as I thought it might be.

I can also do a bit better with hand loading, but, my shooting ability (or lack thereof) masks it to some extent.

[CFJunkie]

charlie b,

i had also to first accept that my shooting ability was a limitation. Then I could decide to work to eliminate the 'shooter induced variations'. It took me over a year of focused effort to discover what portions of my set up provided consistent accuracy and then develop the 'reads' that would tell me that I was being consistent in my set up.
I started with my two .308s I managed to improve my accuracy by over 30% over that time and once I got consistent, my accuracy has been improving at a slower rate over the years since then.
Then I added a Les Baer .223, three 6.5mm Creedmoors including the latest 12 FV, and the latest 12 FV .223.
When I got the Les Baer, I started to tune for exit time and gained a bit more accuracy from that.
All of those were rifles have been pretty accurate at the outset but even then the accuracy with all of those rifles has improved as I used them.

I still have instances when I seem to lose touch with the set up approach but fortunately I can see when the odd shot falls out of the ragged holes I try to shoot.
I usually am able to correct the error and get back to tight groups pretty quickly.
When I was still in the process of learning to be consistent, it took longer. Lately, correction is usually one shot away.

I shoot about 5,200 rounds a year so I have had plenty of opportunity to experiment and to measure my results to document my improvement.
Not everyone is fortunate enough to have the time to devote to such an effort.
Fortunately, I have measured every group I have shot and documented it in detail since 2008, so I also didn't have to learn to keep the records I needed to figure out if I was improving.
Without those records, I doubt I could even answer the question you asked in post #42.

[charlie b]

It was a bit hard for me to admit to myself that the problem was me. Many years ago I could just go out and shoot and the bullets went where I wanted (I am 66 now). But, I also considered MOA to be perfectly fine. Then I stopped shooting rifles for a few decades. Now I have the time and resources to shoot more, at longer ranges, and I expect more from me and my equipment. The hardest part is to fix errors in form that I have had for many years. I do have to say it has been fun.

At first I was not keeping many records. Then, as I realized my errors in shooting, I started keeping them. Technology has helped as I take pictures of every target these days along with reloading and setup notes.

Thanks again for posting your results. Very helpful to us hackers out here.

[charlie b]

Thanks to a bit of experimenting today I have managed to shrink my .308 groups down to .75 MOA on a fairly consistent basis. Now I can work on it a little more and see where I am still screwing up. I had been using a Harris bipod and it just was not working for me. Went to a bench rest and rear bag and am now working on position repeatability. I finally got a series of groups that were fairly consistent instead of a good group followed by two bad groups. And, no, I don't want to spend the money on a Sinclair bipod :)

So, this just confirms that it is me and not the rifle/load. I have a lot of work to do :)

PS thanks again for posting all the good info. I will stop thread hijacking now. :)

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[CFJunkie]

Sounds like you are on the right track.
I'm happy to have helped you a little bit.

Sounds like you made a big improvement in one range session. Keep up the good work.

[charlie b]

I tried the lighter load for the 77gn (22.5 Varget) at book OAL (2.26") and it seems to be a little better than my 23.5gn load. I also did some with a 2.28" OAL (0.020 from the lands) and 23.5gn Varget. The lighter load and longer load were both about equal and a bit better than the shorter, hotter load. Part of the problem is still me. Watching the crosshairs I am good for about .25" of group size (at 100yd), so if the rifle shoots .25 then group size will be .5. The nice thing is that all of the groups were less than .5 except for one flyer. One group was a ragged hole (approx .3") I was shooting at 100yd today cause it was a little breezy.

Next I will try 22.5, 23.0 and 23.5 loads at the longer OAL to see if one is better than my original 23.5gn load.

PS I am also going to try adjusting my bench setup to help get rid of the .25 self induced error. :)

[charlie b]

Went to the range today to shoot a bunch with the 77gn SMK's at a length of 2.28" (0.02" off the lands).

Tried the 22.5gn and 23.5gn Varget loads along with some IMR4166 I just got.

Group of the day was a 0.2" group (22.5gn Varget). But, the other two groups were 0.7 and 0.6

The 23.5 Varget groups were 0.4 and 0.5 The 4166 loads were 0.4 and 0.6

I still think I am causing 0.2" of the dispersion. Also jerked a couple shots today, which kinda bugged me.

So, thanks for the data on the 4166 powder as I think it will be a good alternative to the Varget for me.