Frustrated with recent load development attempts

[Notso]

Ok, so I had an interesting load development session earlier this week and I don’t know what to make of it.  I was specifically load testing my Lapua brass to find a good node for 175 SMKs and Varget.  Some background:  I have a Rem 700 SPS-T in a Manners T4A w/mini-chassis and S&B PMII optics.  I had the “SPS accuracy package” done this past summer by SAC and it is absolutely a tack driver.  But ever since the gun came back from SAC, my previous accurate loads using 175 SMK, 44.6 and 45.0 grs Varget in Lapua brass just never seem to shoot well.  I was even getting some case head separation issues in my 9-10 x fired Lapua brass – but I traced that to incorrect FL die setup where I was over-bumping the shoulder.  So I ordered another 200 pieces of virgin Lapua and decided to re-load develop from scratch since it was essentially a completely different chamber from the factory one.  I’m up to 4 range trips on that brass now and I’m getting nowhere.  

I do have a smoking good load for 168 AMAXs and 175 SMKs but in WIN brass.   They shoot ½ MOA or under almost every time.  This past week when I was load developing again for the lapua, brass – I had some of the good known WIN brass loads left over from a recent TAC match along on this range trip to use as a reference load, which I had never had on previous trips shooting the Lapua loads.

So for this trip, I loaded up 10 rounds each of:
175 SMK
Lapua brass (4x fired, freshly annealed)
Fed 210M
2.820 COAL
.337 Bushing, FL sized in Redding S-type Comp dies
Varget loads of:
44.6
44.7
44.8
44.9
45.0
 
I was sure my node was going to be in there somewhere.  So I started at 100 yds with my reference load of 168 AMAXs (46.0 Varget) in WIN brass to check zero.  1st three were a little high and right for about a .35" 3-shot group:

 
Moved the scope to adjust and shot another 5 with the same 168 AMAX/Win at the same target above, still under 1/2 MOA..  It was feeling like it was going to be a good day.
 
So then I moved out to 300 yds to start my load devel with the Lapua brass and say these results:

 
I didn’t bother shooting the 45.0 load at 300 because it was sucking so bad.  The above are all greater than 1 MOA and close to 1.2.  I didn’t think I was shooting that poorly, so I moved back to 100yds and had my mentor who is a MUCH better shooter than me shoot the rest of the loads over again at 100.  Results are as follows:

 
The last pic was the 45.0 load, 3-shots each.  That’s a 1 inch outer circle and I measured them all at right about 1.2" 5-shot groups.
 
So I’m thinking holy frack, what has happened to my gun.  So to test a theory – I shot the few remaining “reference Loads” in WIN brass I had left to see if they were also shooting poorly now.  I had 3 left of my 168 AMAX load (46.0 Varget) and 175 SMK (45.6 Varget – both in WIN brass.  

 
Both of those shot as expected – the 168 AMAX is .38” and the 175 SMK is .48”.  
 
So….. I’m really at a loss as to why there is no node in there.  I was NOT able to chrono these as my friends Ohler took a shit that day.  But I had previously chrono’d the same strings and they were right in the 2600-2630 fps range (20” barrel), which is right where the 175 SMK load in Win brass is (2630fps).  By the last couple of loads (44.8-45.0) I was just getting some pressure signs (ejector swipe).  But no sticky bolt and no flattened primers at all.  So maybe I can go up a little, or go down below 44.6 and try some more loads.
 
It’s not the end of the world, because I have two really great loads in WIN brass that shoot lights out.  I just hate that I can’t get the Lapua brass to shoot worth a shit.  
 
My next step is to weigh the Lapua brass and do the water measurement and run that data through QL and see where those loads fall on the OBT scale.  Any other suggestions???  I’m frustrated
 

 

[The Mechanic]

Re: Frustrated with recent load development attempts

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> My next step is to weigh the Lapua brass and do the water measurement and run that data through QL and see where those loads fall on the OBT scale. Any other suggestions??? I’m frustrated
</div></div>
That would be my first thought. Each group seemed to string either vertical or horizontal.

 

[Cascade Precision]

Re: Frustrated with recent load development attempts

I will be the dumb one and ask: Did you check your paralax?

 

[Notso]

Re: Frustrated with recent load development attempts

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ogreshooter</div><div class="ubbcode-body">I will be the dumb one and ask: Did you check your paralax? </div></div>
Yep, absolutely. And since I didn't change the scope between the bad shots and when I shot my much better "reference" shots, the groups changed considerably.

I'm beginning to suspect neck tension. I just got done loading another 25 of the Lapua brass to shoot in the am. I'm going to run some loads below and slightly above the charge weights listed above to see if anything tightens up. But I noticed while seating the bullets I was feeling a LOT of force needed to seat the bullets, more than I was ever used to. I'm using a .337 tungsten neck bushing and I measured the necks after sizing are around .335 and loaded necks are like .3385. I pulled the 1st five bullets, ran a mandrel through the necks and then reseated them again. They felt MUCH better. So it will be interesting to see how these shoot. I wonder if I have a bad bushing. It's new, I was using a normal .336 bushing with my previous Lapua brass but I wanted to go up one size for slightly less neck tension, but it seems I'm getting more than the previous one. So we'll see....

 

[Greg Langelius *]

Re: Frustrated with recent load development attempts

You might try an old BR handloading trick to 'manage' neck tension.

Back off the sizing die it only partially sizes the length of the neck. This dates back to the days before bushings, when F/L dies were the whole enchilada.

By reducing the contact area to less then the neck's full length, you can reduce neck tension, and by varying the portion of the neck to be sized, you can adjust it somewhat.

I establish my tension value by attempting to rotate the seated bullet in the neck with thumb and forefinger only. I adjust tension less (die upward) so it will slip, then tighten it back (die downward) in small increments just until it stops slipping.

This allows me to set a repeatable neck tension value. It's easy enough to retest and reset for each loading cycle.

Chargewise, I consider 45.0gr of Varget to be at about the middle of the likely accuracy range for the 175SMK. Paying particular care to pressure signs, I'd suggest adjusting the charge upward in small increments to see if the accuracy improves. Definitely not above 46.0, and up to there with caution. I'd also suggest avoiding rifling contact with peak charges.

Impact stringing is usually an indication that you're not at the node, and/or that something is amiss with either bedding or scope mounting.

Greg

 

[flashhole]

Re: Frustrated with recent load development attempts

Did you compare neck tension and neck thickness to the Win brass? Another thing to look at is the inside of the neck, is it smooth or coarse. I find I can tighten the groups up a bit if I polish the inside of the case neck with a bore brush.

Antoher thing you might try ... can you reload at the range? Cycle/reload the same piece of brass several times and check for repeatability for that one case. If that holds true it may point you to another area in the process.

 

[supersniper]

Re: Frustrated with recent load development attempts

I have found that the Win. cases take a full grain more than the Lapua cases. You may want to dial back your charges and work up from there. Your velocities may work out to be the same but the case capacity differences will dictate the charge weights for each brand. I really like the Lapua cases for the better quality and consistency.

Also, the jump to the rifling will be very different between the Sierras and Hornadys because the ogive are of different designs. Even a bullet weight change in the same brand and style will require a different seating length.

 

[problemchild]

Re: Frustrated with recent load development attempts

After you have tried everything else try XBR powder. I had the same problem with varget and switched to XBR and my groups got small. Just like a barrel is load sensitive I think they are also powder sensitive. And yes the varget worked for me once too then never again.

 

[woodspider]

Re: Frustrated with recent load development attempts

300 yards for node hunt is a good start but a bit short in my opinion. Can you get out farther say 500 to 700 that may reveal a little more truthful data? Ive always found farther the better when looking for the node. I cant believe there is no node in there??? stretch it out and re do the ladder see what you get before assigning blame to the brass or neck tension. If you get no node at extendend ranges then move on to other things.

 

[Dionis]

Re: Frustrated with recent load development attempts

try lower accuracy node 43.0 -44.0 grains of Varget with 175 and Lapua...
also try .335 bushing and remove expander ball.

 

[MALLARD]

Re: Frustrated with recent load development attempts

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: woodspider</div><div class="ubbcode-body">300 yards for node hunt is a good start but a bit short in my opinion. Can you get out farther say 500 to 700 that may reveal a little more truthful data? </div></div> +1 i agree , but you should be able to do allot better then what your doing at 300y.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flashhole</div><div class="ubbcode-body">Did you compare neck tension and neck thickness to the Win brass? </div></div>+1
its surprising your win brass outperforms your lapua

i might suspect neck tension to
goodluck

 

[vonbalkenbush]

Re: Frustrated with recent load development attempts

you're ladder test only covered a 0.5 grn charge range. That is way too small to find a node. Start at about 43.0 grns and bump each succesive charge by 0.3 grn loading only 1 round per charge weight. End the ladder at 45.4 grns. That'll give you this:

#1 43.0 grns
#2 43.3 grns
#3 43.6 grns
#4 43.9 grns
#5 44.2 grns
#6 44.5 grns
#7 44.8 grns
#8 45.1 grns
#9 45.4 grns

Move back to 500 yds. Mark the tips of the bullets with a sharpie (3 different colors) so you only have to walk and mark the shots every 3rd shot. You WILL find a node this way. When you find a node which will show up at two or three different charge weights, then break it down into 0.1 grn increments to cover that range that you found from the first ladder test. Load up about 5 rounds at each charge weight and see which one shoots best. Then take out the chrono so you will know where the node is for that load in terms of MV. Then you can bump your charge up or down for winter or summer so you're bullet will have the proper exit timing from the barrel to stay on the node year round (usually requires 1-3 tenths of a grain adjustment depending on what powder you use). If I did a poor job explaining this let me know? I would be happy to clarify anything that doesn't make sense.

-SBS

 

[BigMahi]

Re: Frustrated with recent load development attempts

At this early in time its not really about neck tension etc.

In furtherance of what Sagebrush & D Ice said:

(1) your making too small increments of .1. Follow SageBrush's advice and once you narrow it to down to a general range, then go in .1 increments.

(2) your initial mistake was starting off at 44+ grains which is the upper end. I use the same reloading components and also have a SPS-T. I started at 43.5 grains and found my accuracy node to be 44.1 (Lapua brass, CCI primers, 175 SMK)

Good Luck

 

[notquiteright]

Re: Frustrated with recent load development attempts

Got to agree-
With lapua brass most find the varget 175grain bullet match around 44 grains of powder.

 

[vonbalkenbush]

Re: Frustrated with recent load development attempts

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: notquiteright</div><div class="ubbcode-body">Got to agree-
With lapua brass most find the varget 175grain bullet match around 44 grains of powder. </div></div>

My go to load with Lapua brass, Varget and 175 SMK's is right at 44 grns as well. Just follow what I outlined in my previous post and you should be good to go. I also should have mentioned to keep an eye out for pressure signs when you get above 45 grns with this combo, especially coming into the warmer months now.

-SBS

 

[vman]

Re: Frustrated with recent load development attempts

Hmmm I shoot 45.1gr Varget with the 175smk in Lapua brass.

I dont really have all that much advice for you besides the following

- Double check your die to ensure you are getting minimal FL sizing
- Start with a ladder test at 300 yards and go with that

You are shooting a lot of ammo and getting nowhere with it.

I know some dont agree with ladder testing, but if you do a ladder with 0.3grain increments at 300 yards you should get somewhere. Perhaps even load up two ladders and fire them seperately.

Did you have your boltface trued? If so you now have a different OAL from boltface to lands. Perhaps seating depth may help to shrink those groups.

 

[Notso]

Re: Frustrated with recent load development attempts

Thanks all for the help and wisdom. I may not have been as clear as I liked in my OP, plus it was long winded and everyone might not have read it thoroughly through.... So let me hit several of the responses:

The bolt face has been trued to the action and chamber recut by SAC

I specifically concentrated on the 44.5-45.0 Varget charge weights because that was where the rifle shot well before the custom work, and I expected to find it again somewhere in that range. I also am specifically looking for a 500-1000 yd load, so the low charge weights in the 43-44 range are stoo slow out of a 20" barrel, so it does me no good to start there.

I used .1 increments because I had already run load development ladders in .5 increments previously and was unsatisfied, so I thought I'd try to narrow it down somewhat to see if there was something good in between.

I chose 300 yds becaue much further and environmental and shooter errors come into play much more the further you go out. So beyond 300, it's hard to tell if the load is just shitty or if the wind/shooter contributed to poor groups.

No I can't load at the range.

I don't understand in the slightest how you get any data out of a single round at each charge weight. What is that telling me?

I typically chrono AFTER finding an accuracy node to see where the MV is for future development. I've found that good ES/SD are not always indicators of good accuracy. I let the bullet itself tell me which load is more accurate. I've seen my best single digit ES/SD loads be the worst groups.

I previously ran a .336 bushing with good results, I might go back to that one. And I DON'T use an expander ball at all. I may try Greg L's partial neck sizing trick.

I always use a bore brush chuck in a drill press to clean the inside of the necks.

 

[Notso]

Re: Frustrated with recent load development attempts

OK, further update. I went back out yesterday (Sat) and shot a load bracketing the one above. I did 5 each of 44.0, 44.2, 44.4 and then 45.0 again and 45.2.

The low weight ones all shot poorly (>MOA) but the 45.0 got a little better and the 45.2 looked like it was showing some promise. They were all loaded at 2.815 COAL. No real pressure signs at all at the top end So I think I'm getting closer and may try to bracket the 45.2 as well as try some seating depth changes around there. I will also chrono them to see what the data looks like. I still will do the QL analysis and see where it looks on the OBT chart.

 

[vonbalkenbush]

Re: Frustrated with recent load development attempts

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body">
<span style="font-weight: bold">I don't understand in the slightest how you get any data out of a single round at each charge weight. What is that telling me?</span>

</div></div>

The barrel moves in a Sine curve when each round is fired. If you run a ladder test with one round per charge weight, you will get 2-3 shots very close together in vertical spread despite the differing powder charges. This will tell you when the bullet is exiting the barrel at a node (top or bottom) in the Sine curve. This is how you find your bullets optimum exit timing from the barrel for best accuracy. Once you have those charge weights, you break down into finer increments from there, overlapping the hightest and lowest charges for the next group of tests. See attached pic below:

[img:left]

[/img]

You can see shot's 7,10,11 and 15 all came in at within 1" of vertical at 500 yds. 10 and 11 were the closest together, so I new I had a stable node right between 47.7 and 48.0 grns. My next trip out I loaded 6 different charges weights, 47.6, 47.7, 47.8, 47.9,48.0 and 48.1 grns all for 5 shot groups. The loads at 47.6 and 48.1 gave me a 0.1 grn overlap from my established node range for the first ladder test. These charge weights all gave me under 2" of vertical at 500 yds. But one stayed under 1" of vertical and that was 48.0 grns. That was my load at 35 F when the test was run. When the temp ran up to 80 F, that charge weight was too much and the bullet was exiting the barrel off the node again. Dropped it back to 47.8 and badda-bing, we were back on the node for summer time temps. That's how I run my load development. Hope that clears it up.

-SBS