F T/R Competition Chrono results for .308 F/TR

Tempest 455

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Mar 4, 2012
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Anyone mind sharing chrono results from .308 loads that shoot F/TR?

The load was Winchester Brass, 175g SMK, 43.5 Varget.

I just tested a bunch of loads and I'm seeing 25-27 ES and SD of 9. I'm thinking that's probably not as good as I should see.

Each bullet was weighed and separated low-high. Cases were exactly 2.005" and checked for capacity and separated.

Runout was .001 or less on every one. Neck tension was around .002" on all of them.

Are these results OK?
 
To be honest, I have no clue what my current or even original ES and SD are and I don't care. It's the results on the 1000 yard paper that count; so how do they perform for you?

Also, your load may be a little on the light side, what kind of MV are you getting and are you looking at shooting MR or LR?
 
To be honest, I have no clue what my current or even original ES and SD are and I don't care. It's the results on the 1000 yard paper that count; so how do they perform for you?

Also, your load may be a little on the light side, what kind of MV are you getting and are you looking at shooting MR or LR?

Results are using a Magnetospeed. MV on average is 2670 last test (using Win brass) and I use these in 1,000 yard shooting. They are super sonic to the target. I'm getting higher velocity w/ Hornday brass (I expected that from case volume) but still thought the ES was high.

I've heard comments that the best shooters and really good scores are from loads that have an ES of 10 or less. Makes sense when you do the math and look at what a 20 FPS difference is at 1,000 yards.

Going to try some Lapua brass and chrono some more.
 
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Results are using a Magnetospeed. MV on average is 2670 last test (using Win brass) and I use these in 1,000 yard shooting. They are super sonic to the target. I'm getting higher velocity w/ Hornday brass (I expected that from case volume) but still thought the ES was high.

I've heard comments that the best shooters and really good scores are from loads that have an ES of 10 or less. Makes sense when you do the math and look at what a 20 FPS difference is at 1,000 yards.

Going to try some Lapua brass and chrono some more.

I'm sure you're correct about ES and SD and all that, I've never bothered to measure mine and I think my ammo does pretty well.

On the other hand, I ran your numbers through JBM just for fun and that bullet is barely supersonic at 1000 yards. If your goal is to be competitive at that distance, you're going to want to increase that velocity.

My personal parameters call for a minimum of Mach 1.25 at 1000 yards in the coldest temperature I will compete in. For that I use a better bullet than the 175SMK, more powder and a 32 inch barrel. My reasoning for Mach 1.25 is that is the onset (event horizon) of the transonic passage disturbance area; I like to stay above that. So my 180gr JLK LBTs pop out of my 32 inch barrel at 2850FPS.
 
You should probably go up to the next node with your load, likely something approaching 44.5 gr of Varget BUT as always work up to that. If your throat is short or you are jamed or any other of hundred variables you may get pressure sooner than expected.

Just run Winchester brass.
 
I'm sure you're correct about ES and SD and all that, I've never bothered to measure mine and I think my ammo does pretty well.

On the other hand, I ran your numbers through JBM just for fun and that bullet is barely supersonic at 1000 yards. If your goal is to be competitive at that distance, you're going to want to increase that velocity.

My personal parameters call for a minimum of Mach 1.25 at 1000 yards in the coldest temperature I will compete in. For that I use a better bullet than the 175SMK, more powder and a 32 inch barrel. My reasoning for Mach 1.25 is that is the onset (event horizon) of the transonic passage disturbance area; I like to stay above that. So my 180gr JLK LBTs pop out of my 32 inch barrel at 2850FPS.

What elevation you shooting at? I've been fine at this velocity at 1,100ft.
 
Well that depends. Last month was shooting at 6600ft elevation and my bullets were coming in above Mach 1.5. This past weekend I was shooting at 38 feet elevation (probably closer to 42 on top of the mound, and the bullets were coming in right above Mach 1.3.

If you think you're fine with your load, then I don't understand why you are asking questions about your ES and SD.
 
OK let me rephrase my original question and maybe I did not ask it correctly:

Not even taking the velocity in question, just the ES. Does that much ES illustrate something wrong in the reloading? I'm coming up w/ a spread of 9" at 1,000 yards just based on the ES.

I'm weighing the brass and separating, trimming all to the same length. All the bullets were weighed and were 175g exactly. Powder was 43.5g exactly. Rounout was .001" at most. The rounds I checked had neck tension of around .002. I would not expect an ES of 25-27?

Now on some different Hornday brass I did see of 10 on one lot but that was the exception.
 
I can't speak about the ES/SD of handloads yet, as I'm just beginning the reloading process myself. However, I have used a variety of different commercial loads in F-T/R competitions at ranges from 300 to 1000 yd. Most factory match ammo such as FGMM 175s, Black Hills 175s, CorBon 175s, etc., will give you ES values in the neighborhood of 35-50 fps, sometimes a little more. The SDs will run from around 10 to the low teens. The ammunition I have used with the best results in competition is the Applied Ballistics 175 gr Tactical load. Because the charges in it are individually weighed, along with the higher BC 175 gr Berger Tactical bullet and generally much more care put into it's preparation, it routinely gives me ES numbers in the low to mid teens and SDs below 10. This load is running between 2750-2760 fps from a 30" barrel. As long as I don't do anything stupid behind the rifle, this load has worked very well out to 1000 yd. In contrast, I shot FGMM 175s at our last 1000 yd match at Camp Pendleton (elev. ~ 420 ft). This load also runs just above 2750 fps out of the same rifle. The wind conditions were pretty challenging with rapidly shifting headwinds from 10:00 to 2:00 at about 13-16 mph, with gusts over 20; however, I've shot the AB175 load under similar conditions plenty of times and done reasonably well. With the FGMM 175s, it was a bloodbath. Many 8's high and low, just all over the place vertical. Although I'm sure the wind had something to do with that, I also believe the load was a big factor. At 2750 fps, the SMK 175 is going just under Mach 1.1 at 1000 yd. When you add in the 50 fps ES, it just isn't a recipe for success. Unfortunately, it was all I had, so I used it. The tighter you can get your ES/SD values, the better off you will be. As XTR mentioned, you can probably get the speed up a little as well by using somewhere in the range of a grain more Varget (as long as it's SAFE in your setup!). 44.5 gr of Varget pushing an SMK 175 has been known to be a pretty good performer for quite some time. Good luck with it.
 
As XTR stated; you are a little light on your load unless your bullet is way down in the case ( due to short throat). If you are shooting paper targets with NRA SCORING RINGS and your s.d. is too broad, you may be good at calling wind but a perceived 10 at either corner of the bull, say at 1 oclock 11 oclock 5 oclock or 7 oclock will throw you a 9 instead of a 10 due to the vertical spread. Some powders do better with a full case rather than a reduced charge. Experiment with several loads to get you s.d. down around 6-7 or better.
 
To be honest, I have no clue what my current or even original ES and SD are and I don't care. It's the results on the 1000 yard paper that count; so how do they perform for you?

Also, your load may be a little on the light side, what kind of MV are you getting and are you looking at shooting MR or LR?

I agree, the actual accuracy is key.

I run Varget and the 43.5 grains of Varget seems about right. Each barrel is different. I noticed a 50-75 FPS change in switching from a Remington 700P to my GA Precision Bartlein barrel. I was amazed that despite an increase in barrel twist, my velocity went up.

Also, I do not think the Extreme Spread of 25-27 FPS is something to worry about since most chronographs are not that accurate. At 25 FPS, you are talking about a 1% difference in speeds. I doubt that the chronograph is THAT accurate given all of the variables.
 
Thanks for the feedback/comments. I will try some groups this weekend at 44.5g Varget. Last time I checked, I was getting 2735-2753 FPS with that load.

Was using 43.5 because my rifle seemed to like it.
 
I agree, the actual accuracy is key.

I run Varget and the 43.5 grains of Varget seems about right. Each barrel is different. I noticed a 50-75 FPS change in switching from a Remington 700P to my GA Precision Bartlein barrel. I was amazed that despite an increase in barrel twist, my velocity went up.

Also, I do not think the Extreme Spread of 25-27 FPS is something to worry about since most chronographs are not that accurate. At 25 FPS, you are talking about a 1% difference in speeds. I doubt that the chronograph is THAT accurate given all of the variables.

Twist for the most part has no bearing on effecting velocity.

43.5gr. of Varget behind a 175MK I clocked thru one of our barrels on a AW rifle built by AI/Tooley. With a 24" finish length the velocity was in the 2620fps. range which is normal. I clocked some factory Black Hills ammo with 175gr. bullets and they averaged 2627fps.

My good working every day and consider close to max. for 175gr. bullets is 44.0.

Becareful going hotter than that. What throat is in the chamber etc...can effect pressures and most of you/us are not running a standard .308win. Saami spec. chamber.

Looking at the Hodgon website they list a starting load at 42.0 which gave them 2583fps and a max load of 45.0 which gave them 2690fps.

I'll ask the OP what finish length is the barrel you are running?

Later, Frank
Bartlein Barrels
 
Twist for the most part has no bearing on effecting velocity.

43.5gr. of Varget behind a 175MK I clocked thru one of our barrels on a AW rifle built by AI/Tooley. With a 24" finish length the velocity was in the 2620fps. range which is normal. I clocked some factory Black Hills ammo with 175gr. bullets and they averaged 2627fps.

My good working every day and consider close to max. for 175gr. bullets is 44.0.

Becareful going hotter than that. What throat is in the chamber etc...can effect pressures and most of you/us are not running a standard .308win. Saami spec. chamber.

Looking at the Hodgon website they list a starting load at 42.0 which gave them 2583fps and a max load of 45.0 which gave them 2690fps.

I'll ask the OP what finish length is the barrel you are running?

Later, Frank
Bartlein Barrels

Barrel is 24" and gun is a Savage 10BA.

I have also tested BHA 175g and it was very close to my 43.5 Varget load.
 
27fps is more than ideal for a competition load, but is well within the bounds of good factory ammo. If it shoots well, just take it to 1k and see what kind of elevation it holds. If you want to get the ES down, I'd try putting some more Varget in that case and maybe fiddle with seating depth an primers. I'd be surprised if that ES did not come down at the 44.5gn range.

I ran 45.5gn with 175 SMK's in Lapua brass with a 210(M) for 2,760fps, ES: 12, SD: 6. that was a thumper of a load, and surely over SAAMI MAP.

My other load was a 178 A-Max over 47.5 RE17 in Win brass and 210(M) 2,680fps, ES: 17, SD:9. This was one of the most accurate loads my SPS and I ever found.

Both loads were out of a 26"bbl.
 
Thanks for the feedback. Here is an update on this:

First off, I'm ashamed I did not catch these issues. I'm pretty OCD when it comes to measuring. I saw the thread on another topic about digital scales. Got me thinking, how accurate was mine? Up to this point, I thought my Hornday scale I was using was accurate. I did some loads this weekend and loaded all of them all this time w/ the RCBS 505 and checked against the Hornday. The Hornday was all over the map. So I loaded all my rounds w/ the RCBS beam scale.

When I was seating the bullets, I was checking COAL w/ my digital caliper. I loaded around 50 rounds and when I was done I went back and checked a few and they were way off. Like .010-.014" in some cases. So I got out a standard dial vernier caliper (which is OK but not the best) and verified the digital was off. At this point I got out my 3" Starrett Micrometer (which is dead nuts accurate). The digital caliper indeed was off and no idea for how long. I went back and checked previously loaded rounds which I (thought) I meticulously loaded to the correct length and they were off. So I loaded every round using the Starrett Mic.

Went to the range today and chrono'd again w/ these changes on the Magnetospeed. Couple of really interesting things came up. I wanted to see what grouped best at 500 yards. So we shot all lots w/ the chrono on and compared to the groups. I had been using 43.5 Varget because it seemed to work well. Today I found that 44.0g grouped best at 500 yards. Even better was, the 44.0g lot had an ES of 5, which I liked a lot bettrer than 25.

We are very eager to see how this shoots at 1,000 now. Looks like I'm sticking w/ the beam scale and mic now for loading my rounds.
 
I load on a RCBS Chargemaster but I check with beam scale I was going to suggest primers but looks like you are on the right track, FYI my 175 SMK load is 44.6 of Varget CCI BR2 primers in winchester brass my ES is 8 so cant complain. This load is running 2735 out of a 22" Krieger @ 2250 ft
 
I typically run different loads at 100-600 and 800-1000 yards. No need to beat rifle up with fast loads at 600 yards. Its all about accuracy there. At a 1000 you need accuracy and very low differences in velocity.

My goal for any 1000 yard low is extreme spread of less than 10fps for ten rounds
 
When I was seating the bullets, I was checking COAL w/ my digital caliper. I loaded around 50 rounds and when I was done I went back and checked a few and they were way off. Like .010-.014" in some cases. So I got out a standard dial vernier caliper (which is OK but not the best) and verified the digital was off. At this point I got out my 3" Starrett Micrometer (which is dead nuts accurate). The digital caliper indeed was off and no idea for how long. I went back and checked previously loaded rounds which I (thought) I meticulously loaded to the correct length and they were off. So I loaded every round using the Starrett Mic.
.

I am not sure using just a micrometer to measure the oal is that accurate. I use a mircometer and a Hornandy insert for the caliber which measures from the ogive/shoulder interface. The tips on SMK's can vary a bit which is not indicitive of your real OALor seating depth which is what matters. Get the hornandy caliber insert and you will see the real difference in your true oal...otherwise you'll be chasing your tail on that dimension all over the place, and your seating depth will vary all over too, along with your pressures. The seater die pushes against the ogive, not the tip, so seat off the ogive which is more consistant than the tips.

Here is the link to the insert.

Hornady Lock-N-Load Bullet Comparator Body
 
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I am not sure using a micrometer to measure the oal is that accurate. I use a mircometer and a Hornandy insert for the caliber which measures from the ogive/shoulder interface. the tips on SMK's can vary a bit which is not indicitive of your real OAL that matters. Get the hornandy caliber insert and you will see the real difference in your oal...otherwise you'll be chassing your tail on that dimension all over the place. the seater die pushes agaisnt the ogive, not the tip.

Understand that's probably the way to go but the point was, the caliper was off. I've got it figured out my ES is very low now.
 
OAL is 2.800. I varied it from lower to higher and it shot best group at 500 at 2.800. Gun is Savage 10 BA and chamber seems to like that length.

Did 1,000 yard match few weeks ago and wind was horrible but the vertical was much better than last time out.
 
I typically run different loads at 100-600 and 800-1000 yards. No need to beat rifle up with fast loads at 600 yards. Its all about accuracy there. At a 1000 you need accuracy and very low differences in velocity.

My goal for any 1000 yard low is extreme spread of less than 10fps for ten rounds

+1.........Below 10 ftps for 10 shots is what i try to get also. I tested a 185gr load yesterday but only shot a 5 shot group but the ES was 5 and SD 2 on the Ohler 35. Im gonna shoot a 20 shot string and see what happens.