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Evaluate my ladder test & groups. 300 yds

Goin'Hot

Gunny Sergeant
Full Member
Minuteman
Nov 14, 2008
2,271
56
Central, Ohio
Went out today with the 300 NM 40° Imp to test some forming loads and do a ladder test with the 210 Bergers and H1000. The ladder test is strange to me because if you exclude one shot (87.5 gr) I only have a vertical spread of 0.592" C-C. It really makes it difficult for me to choose where to go from here. Below the pic, I will post the velocities.
2012-02-05_16-18-09_491.jpg

86.0 - No data..88.5 - 3210.....91.0 - Did not shoot
86.5 - 3162......89.0 - 3215.....91.5 - Did not shoot
87.0 - 3185......89.5 - 3224
87.5 - 3219......90.0 - 3276
88.0 - 3207......90.5 - 3280

Starting at 88 grains, the velocity went down and between 87.5 and 89.5 grains, the velocity was stagnent. I'm guessing that 87.5 grains should be my effiency limit. Is this correct? It takes another 2.5 grains of powder to see any REAL velocity increase. I know these are only 1 velocity per round but, at least its something.

I also shot 4 groups to find a load when forming brass with the 210's. I like group #2 but, the groups have more horizontal movement than I was expecting. Does this indicate a potential rifle issue or can it just be attributed to the wind? At my shooting position, I had a 5-8 mph wind running from 2 - 7 oclock. I was shooting across a "wind tunnel" 2/3 of the way to target. All shots were fired at 300 yards prone. Group 4 was too hot to shoot on a regular basis. Whatcha think?
2012-02-05_16-30-58_317.jpg
 
Re: Evaluate my ladder test & groups. 300 yds

I would say you could have a problem with your barrel not being floated.If your first shot of the string was at point of aim and then they started to string to the right. You say the wind was 2 to 7 oclock, your impact would strike left not right. Just my opion.
Good luck, Chris
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: yotedog65284</div><div class="ubbcode-body">I would say you could have a problem with your barrel not being floated.If your first shot of the string was at point of aim and then they started to string to the right. You say the wind was 2 to 7 oclock, your impact would strike left not right. Just my opion.
Good luck, Chris </div></div>

The barrel appears to have plenty of clearence.
2012-02-03_15-49-41_98.jpg


I know the last shot in group 4 was in the dot and the first shot was on the right. Same with group 3. Group 1 had the first 2 shots below the orange dot and group 2 was nearest the dot for the 1st shot and then the third shot went right.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Cigarcop</div><div class="ubbcode-body">You need to shoot the ladder test out further than 300 yrds, then you will see your vertical. </div></div>

I'll try and get out to 450 or 500 yards and repeat. I've typically seen a vertical spread at 300 with all of my other rifles.
 
Re: Evaluate my ladder test & groups. 300 yds

If the intent of the ladder test is to find a 3 consecutive shot node with minimal vertical dispersion, then I'd say your 89.5 - 90.0 - 90.5 node will be hard to beat. I
would load 5-shot groups at 90.0 gr. at different seating depths and see which seating depth affords the tightest group.
 
Re: Evaluate my ladder test & groups. 300 yds

Looks like 89.5-90.5 are the tightest. Like Squarenut said, go from there. Although there is minimal vertical dispersion, as long as you feel you had good form for every shot, no reason not to. But, if you have longer than 300 to work with, that woul dbe the optimum scenario.
 
Re: Evaluate my ladder test & groups. 300 yds

Went back out today to test seating depth again. Had hard bolt lift due to a 20 degree temp increase so, it's back to the drawing board. 4 shots on each.
2012-02-15_15-49-39_553.jpg
 
Re: Evaluate my ladder test & groups. 300 yds

I agree with the above poster. If you want to to go further, load 3 rounds of each .1 increment between 89.5 to 90.5 (for a total of 30 rounds). Be sure to space the shots for cooling and max consistency.
 
Re: Evaluate my ladder test & groups. 300 yds

I had this happen with my 30-375R and 230 Berger hybrids, LOL! 4 of the shots in a ragged hole at 300Y. Some rifles are too fricken accurate to do a ladder test at 300Y with. Nice problem to have though
wink.gif


I ended up using the load with lowest SD then confirmed accuracy at 960Y with a 3.6" 5 shot group, The vertical was only 1.6"!

Your Wildcat is a screamer!

+1 on letting the barrel cool.

So far I'd be inclined to pick 86 grains to start checking extreme spreads with.
 
Re: Evaluate my ladder test & groups. 300 yds

+1 steve

i can't agree with .1 increments , you can have up to .5 grain difference in charge weight and still exit over a node , so i dont see the need for .1 increments

20 degree change affecting bolt lift ? what was the temp you intially tested your loads in ?

personally... i dont think 20 degree can change your pressure that significanlty, to move a safe load from an unsafe load.
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Trevor</div><div class="ubbcode-body">what was the charge weight. if you were running 90 i would try 89.5 the lack of vertical between 89.5 and 90.5 is impressive. </div></div>

Charge weight has been 89.5 grains. I had a very strange occurance yesterday. My first shot had resistance on bolt lift and a very stiff cam when the brass was extracted. I knew I shouldn't shoot the other 11 rounds but, I snuck out of work and wanted to shoot. All 12 rounds of this ammo had the same resistance and hard cam. When I shot the load previously, the primers were starting to flatten but, I wasn't scared to shoot the rest of them. Unfortunately, I didn't have the time to set up my chronograph on this outing so, I don't have any velocities to look at and try and figure this out.

I'm going to try and sneak out again tomorrow and drop down to a max load of 88.8 grains. I have a shoot this Saturday so, I need to get choppin'.
 
Re: Evaluate my ladder test & groups. 300 yds

I had gone out the previous weekend and shot these. Temp then was 20 and temp most recently was 40.

Top left is 0.120" jump, 0.080" jump, 0.040" jump and top right is jammed. All groups have 4 rounds.
2012-02-12_17-57-05_20.jpg

Bottom row are my forming rounds where they need to jam to assist in proper shoulder formation. I only got to shoot at 100 yards due to the wind which was shifting 8-12 and gusting to 20 mph.
 
Re: Evaluate my ladder test & groups. 300 yds

Steve

Every time you talk about that frigg'n 30/375R you make me hate you more.
laugh.gif
Dayum that rifle shoots like crazy. Keep talking about it and I'll have to start buying components to build one.

Jeffvn
 
Re: Evaluate my ladder test & groups. 300 yds

You have not mentioned it so I'll ask. When you are getting the sticky bolt, what do the base of the cases look like? Are you seeing ejector marks on the brass, flattened and cratered primers? If yes, then you are seeing pressure signs. Since its not hot yet by any means in Ohio, you may need to reconsider the load altogether. If not, then its something else.

It looks like your wildcat is going to be a hammer if you can get the load sorted out. Good luck. I have always had problems developing loads in the winter and then using them year round.

If you can (easier said then done for most) try to do the development at 400+ yards; the vertical dispersion in loads really shows up at 400 and beyond.

Jeffvn
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">You have not mentioned it so I'll ask. When you are getting the sticky bolt, what do the base of the cases look like? Are you seeing ejector marks on the brass, flattened and cratered primers? If yes, then you are seeing pressure signs.
Jeffvn </div></div>

That's the tricky part. I have no ejector. The primers are fairly flat and i'm used to shooting loads in other rifles with flat primers as long as the ejector doesn't start to imprint on the case head. Since I have no ejector in this rifle, I was using bolt lift and primer appearence to tell when I needed to back it down. The primers in these loads on previous outings still didn't show any flow around the FP but, on this occasion, they did.
 
Re: Evaluate my ladder test & groups. 300 yds

Went out today and shot more loads from 86.6 - 88.8 in 0.3 increments. I had annealed the brass from the last firings and the bolt was tough to close before firing. The bolt was tough to open after firing as well. I took the brass home and used steel wool on the bolt face to remove all the brass from it. Putting the brass back in the chamber and closing and opening the bolt, it would fill the bolt on one side with brass again. I resized the brass to get rid of the closing resistance and stop putting brass on the bolt face but I really don't feel comfortable with what i'm seeing.

To recap, my initial pressure/ladder test showed pressure (shine on the headstamp) that made me stop at 90.5 grains with brass that was fire formed one time. I worked with 89.5 for group development and was only seeing MINOR pressure signs. I went out a second time to do a seating depth check (using the same brass). Today I went out and my 86.6 grain load was showing pressure with primer flow around the FP and a VERY STICKY bolt. I am 1.9 grains under the load I had decided on earlier so this is VERY puzzling.

I am using H1000, Norma brass, 210 Bergers and Fed LR Mag primers. Any ideas? Initial pressure tests were done jammed and I am now 0.040" off the lands so, pressure SHOULD be lower.
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ouch!!!!</div><div class="ubbcode-body">Check your chamber depth, your brass may have grown. Making he bolt closure tough and spiking the chamber pressure. </div></div>

Shouldn't this be taken care of when sizing?
 
Re: Evaluate my ladder test & groups. 300 yds

Not in a die. You need to measure things. Get a sized case with no primer, powder or bullet and see if it gives the hard sticky cam your talking about.
 
Re: Evaluate my ladder test & groups. 300 yds

I took some of the brass that was VERY stiff in / out today and ran it through my sizer. No resistance on the bolt after sizing. What troubles me is the amount of brass that accumulates on my bolt face when the bolt is difficult to lift.
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Goin'Hot</div><div class="ubbcode-body">I took some of the brass that was VERY stiff in / out today and ran it through my sizer. No resistance on the bolt after sizing. What troubles me is the amount of brass that accumulates on my bolt face when the bolt is difficult to lift. </div></div>
Your essentially shooting a 300Win with 210 Bergers at 3200fps.
Your right to think you are hot.

Shoots nice man!
 
Re: Evaluate my ladder test & groups. 300 yds

Well, I went out today to form some more cases and "find pressure" again with the cases I already have formed. I had been shooting 89.5 grains 40 off the lands and had the issues described above. Today, I started at 86.2 and went up to 88.6 grains in 0.3 gr inc. The first round had resistance when opening the bolt. This is what the bolt looks like after 3 firings with the old brass and a max on this photo of 86.8 gr.
2012-02-18_09-58-13_654.jpg

and this is what it looks like after I clean it with some steel wool.
2012-02-18_10-01-25_711.jpg

It's kinda hard to see but, the forth round of the day was shot on a clean bolt face and you can make out the word "Norma" on the bolt.
2012-02-18_10-06-10_231.jpg


I'm going to attribute all of these issues to soft brass and an idiot overloading them. I have settled on 87.0 grains after this work up today in less than favorable wind conditions. All I need to do now is vary the seating depth to try and dial it in on a good wind day. Previous velocitys on 89.5 grains netted me 3245 fps and 87 grains gets me 3175. 75 fps is not worth a $2 piece of brass after 3 firings.
2012-02-18_21-24-51_696.jpg

The group on the top right is 230 Bergers over N570. I went out to find pressure and didn't put enough powder in. The 7 shot group can be covered with a quarter and the charge weight runs from 77-83 grains in 1 grain increments. I have also dropped my forming load down to 84.5 grains from a previous 86. The new forming load gets me about 3105.

Now I need to get out with the new load and see how many firings the brass will stand up for.
 
Re: Evaluate my ladder test & groups. 300 yds

great picture on the Norma Brass on the bolt face. Agreed that slice of velocity is not worth expensive brass, especially if you can find an accuracy node close by.

Jeffvn
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">Steve

Every time you talk about that frigg'n 30/375R you make me hate you more.
laugh.gif
Dayum that rifle shoots like crazy. Keep talking about it and I'll have to start buying components to build one.

Jeffvn </div></div>

Haha, no need to hate
smile.gif
I could probably try to do that again 20 times and never get those results again. I was smiling at the time though. I'm hoping the next barrel shoots like this one does.
 
Re: Evaluate my ladder test & groups. 300 yds

Goin'Hot,

Are you working with the same lot number of powder? 1 lb jugs ?

Twice now I've had to work up a new load when I ran out of the original 8 lb jug I had used for a long time, both different powders and different rifles. One was way to hot and the other 100fps slower.
 
Re: Evaluate my ladder test & groups. 300 yds

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: steve123</div><div class="ubbcode-body">Are you working with the same lot number of powder? 1 lb jugs ?</div></div>

All out of the same 8#'er. I've had it for the better part of 2 years. I use it in my Edge as well but this Norma is my "flavor of the week".

I added a 1# container I purchased from a guy at a very reasonable price and I shook and turned the jug to mix it all together. This jug has been very consistant in my Edge.

I'm going to try and sneak out of the shop tomorrow and test 3 loads at different seating depths. I should have time to set up the chrony as well. I'd also like to keep track of 1 piece of brass and load it with this new load and keep track of the # of firings on it to see if anything goofy crops up. The bolt lift with all of the above loads was just like there was nothing there. I may put a mark on the headstamp with a majic marker to track the one piece. I figure if I shoot it everytime I take the rifle out, I should get to 10 firings pretty quick. The nice thing with having no ejector is the brass stays nice and clean. Run a piece of steel wool around the neck to clean it up and load it again.