Need advice ?

[seasprite]

Hey guy's been fighting some inconsistent  groups with my 168gr loads sometimes there dead balls accurate and other times 2.00" and worse. Out of frustration pulled some down and started checking various things and found using Hornady's compairiter  I found that the bullets varried in length from .633 to .660.

 

Soo should I try loading for same depth the bullet base is seated in the case? Have any of you guy's tried this and how did it work?

 

To me seems this would give more consistent pressures if all this makes any sense.

[planeflyer21]

That's a HUGE variation.

 

What is the make of bullet?  

 

I hate being anal about loading but if the maker is that inconsistent on bullet length, I'd find another brand.  Even my "Midway blemished bullets" don't vary that much.

 

If they were that far off, they'd be separated by length and weight (can't see the weights being that close either), then work up loads for each batch.

[Tripledeuce]

   To me, It sounds like you have a varity of "batches" of mixed bulletts.   If they all weigh the same, then the varation can only come from different set ups of the forming dies.   Back when Sierra bullets were in So. Cal. I used to go down and buy "seconds" by the pound.

    Found one batch of .277 bullets that varied from 130 grain to 140 grain.   Since I had 20 pounds of them, I sorted then by weight.   Made a big difference!

 

   Respectfully

    Terry

Edited August 25, 2013 by Tripledeuce

[seasprite]

That's a HUGE variation.

 

What is the make of bullet?  

 

I hate being anal about loading but if the maker is that inconsistent on bullet length, I'd find another brand.  Even my "Midway blemished bullets" don't vary that much.

 

If they were that far off, they'd be separated by length and weight (can't see the weights being that close either), then work up loads for each batch.

 

These are horndy A-max bullets and yea it took me by surprise that there would be that much of a difference. I haven't weighed them yet but I'm going to.

 

 

   To me, It sounds like you have a varity of "batches" of mixed bulletts.   If they all weigh the same, then the varation can only come from different set ups of the forming dies.   Back when Sierra bullets were in So. Cal. I used to go down and buy "seconds" by the pound.

    Found one batch of .277 bullets that varied from 130 grain to 140 grain.   Since I had 20 pounds of them, I sorted then by weight.   Made a big difference!

 

   Respectfully

    Terry

 

I'm thinking along this line hear because as I measure them I,m coming up three distinct groups one around .633 and .644 and .660

 

I guess to figure things out I'm going to load a test batch and see which bullet length performs the best. Then make adjustments for the other lengths of bullets and see how that goes.

 

Sierra is just 50 miles down the road from me I really need to get there and check there blem barrels and take a tour of the factory.  

[planeflyer21]

The forming dies makes sense.

 

A couple of people told me to separate match bullets by the diameter size of the exposed lead on the base, as that shows which die that bullet went through.

[survivalshop]

I think some where here , it was said that there 168 gr. match bullets ,varied also . I have some & have not got around checking them yet

 

Polymer tipped bullets ?

 

I get anal by weighing my brass & put them in batches by weight . Not a bad idea with bullets , I may start looking a little closer at them also.

[MONTANA308]

I haven't heard much good about the A max bullet lately. And with thoses measurements your givin that's just ridiculous. That's suppose to be there match bullet! The long range guys I have been shooting with wont use them. all Berger or Sierra.

[seasprite]

I think some where here , it was said that there 168 gr. match bullets ,varied also . I have some & have not got around checking them yet

 

Polymer tipped bullets ?

 

I get anal by weighing my brass & put them in batches by weight . Not a bad idea with bullets , I may start looking a little closer at them also.

 

Yep there the polymer tipped

 

I just got done loading the test batch of 15 rounds to see which one shoots good 3 five round groups for each bullet length that I came across. I'm hoping that one will be the accuracy node that I came across before. Then make adjustments to the other groups of bullets to hopefully match the first test. Make sense :eek13: This batch of brass is .9gr difference for 20 pieces, I divide mine up in 20 piece lots.

 

I did weigh the bullets and there wasn't but a .2 or .3 gr difference between them with one oddball that was .5

 

 

I haven't heard much good about the A max bullet lately. And with thoses measurements your givin that's just ridiculous. That's suppose to be there match bullet! The long range guys I have been shooting with wont use them. all Berger or Sierra.

 

With supplies the way they are right now I'm stuck with what I got so hopefully I'll get this worked out and be back to shooting MOA or better groups with this rifle again. I'm defiantly going to go down to sierra when I get a chance to see if they have any stock.

[MONTANA308]

Ya I hear ya on supplies any loaded bullet is better then not. I've been lucky and my LGS has and a good supply of Sierra and Bergers so I have been lucky in that department. I hope you get them shooting like ya want. Had pretty good luck with accuracy out of the 165 Sierra game king if you can find any matchkings. Then ya have a hunting bullet as well.

[mineralman55]

Not to jump on Hornady, but I've had quality control issues with the Hornady 168 BTHP in recent years. After using the Hornady 168 grain .308 BTHP for years and getting excellent groups with them, about two years ago those groups started to open up wildly. I found some of the batches of these bullets were 0.008" longer than others. I asked Hornady about it and they replied with no knowledge about it. I just buy the Sierra 168 BTHP now. They cost a few bucks more, but they seem to be more consistent. Too bad, I really did like the Hornadys!

[planeflyer21]

Wow...a difference of 0.008" and your groups opened up wildly.

 

No wonder seasprite is all over the map!

[MikedaddyH]

I also noticed that with Hornady 115gr hpbt which is my go to bullet for 6.8spc that the length varied .003 to .005 in a box of 100. I sorted the bullets to length. But never thought much about it after that.

[survivalshop]

Could be just the polymer tip, itself , that's at different lengths . 

 

One would think , unless the tip is interfering with the seating plug of the die, they should seat into the case about the same .

 

Most seating plugs use the bullets ogive to seat the bullet & if the tip was not interfering with the seating stem/plug ,they should not be any deeper in the case . Unless the bullets are indeed out of spec's.

 

I have to check my Hornady bullets , because I use a lot of them for different calibers .

Edited August 26, 2013 by survivalshop

[seasprite]

Could be just the polymer tip, itself , that's at different lengths . 

 

One would think , unless the tip is interfering with the seating plug of the die, they should seat into the case about the same .

 

Most seating plugs use the bullets ogive to seat the bullet & if the tip was not interfering with the seating stem/plug ,they should not be any deeper in the case . Unless the bullets are indeed out of spec's.

 

I have to check my Hornady bullets , because I use a lot of them for different calibers .

 

 

 

That gives me around .027" difference which to me seems pretty excessive, as far as the seating plug goes I don't think I'm having any issues there because it leaves a slight ring around the ogive at same place on every round that I seat.  

[seasprite]

Alrighty finally got to go to the range for an hour today, this waiting till I have time is for the birds I wish I could step out in the back yard like some of you guy's. Well enough of me crying and on to the results.

 

 

 

As you can see the .633" bullet length seated to a ogive depth of 2.176" (all bullets lengths seated to this ogive length) did the best in grouping at 100 yards. The .645" bullets seam to scatter and came back some with the .660" bullets. There was a point of impact shift between all three bullet lengths. So I guess my next step is going to be to base all my seating off the .633" length so the .645" will be seated to 2.188" ogive length and 2.203" respectively. One problem I might run into is the 2.203" might be over mag length for my Pmags but should still fit my DPMS steel mags.

 

Man I can't help but wounder if I'm totally off the beaten path here or on the right track any words of wisdom from you guy's?

 

Oh and the target in the upper left corner is my 147gr pull down plinking load dam near out performing my match load and I didn't even try that hard on it go figure. 

 

[Tripledeuce]

   When I used to weigh all my match loads, I held my brass to .5 grains, and found that a difference of 2 grains to be a HUGE difference with the bullets I was then using.  Most bullets, at the time, were Speer or Sierra's, and were held withen a tenth, in a typical box of 100.

      I''v been using Hornady AMax 6.5 140's in my 260 Rem AR, and it groups near an inch,or under ,most of the time.   I'll try to get some shots of some groups i'v got, and post them tomorrow.

    Respectfully

    Terry

[survivalshop]

I weigh all my brass for target / hunting loads  &  load them in batches that way. I have found through using a Chronograph , variances in brass volume capacity  = pressure changes , which equate to changes in Velocity , which effects grouping & may also shift point of impact .

 

A chronograph is a very valuable tool in load development . I see that now , that I have one & went for thirty years with out one .

 

If I remember correctly , the PMag should take a longer COL. . Have you tried to seat them using a std. COL , like all of them 2.800" or some thing like that . ?

 

 

[seasprite]

I weigh all my brass for target / hunting loads  &  load them in batches that way. I have found through using a Chronograph , variances in brass volume capacity  = pressure changes , which equate to changes in Velocity , which effects grouping & may also shift point of impact .

 

A chronograph is a very valuable tool in load development . I see that now , that I have one & went for thirty years with out one .

 

If I remember correctly , the PMag should take a longer COL. . Have you tried to seat them using a std. COL , like all of them 2.800" or some thing like that . ?

 

This is my line of thinking as far as bullet length goes, longer bullets seated to the same as the shorter bullets means your going to have more bullet in the case and less case volume as a result and a rise in pressure.

 

I keep my brass within 1.5gr of each other for 20 piece lots or one mag so I think I'm good to go there. You know ever since I found this problem with the different lengths I haven't ran the cronny for this trouble shooting process maybe I need to change that.

 

I measured the Pmag and they can take up to 2.820" and still feed reliably, my DPMS mags can take 2.840 which should be good for the .660 length bullets. The .633 bullets seated at the ogive length of 2.176 is pretty much 2.800" +or- .005" due to tip variances.  

 

Looking at what you said that I highlighted in red makes me think that I'm on the right path thanks survivalshop  I'm going to push on and load the next batch of test rounds should only be 15 rounds (3-5 round groups) since theirs only 3 different bullet lengths to deal with.

[survivalshop]

Just don't do  like I did last weekend in testing the Barnes LE bullets . I moved them to the back seat & they were in a slip top case ( which I normally don't use ) & I thought I had them secure , but first braking & it was " 52 pick up " ,so I weighed them all , thinking I would see the changes in weight of the powder charges . Not so , the charges were too close & I have no Idea what was what & my ES &SD & Vol. showed this .

 

I have some of the 168 gr, Hornady match bullets & have used them & they printed pretty good @ 200 yards. , I may have a photo of the target some where. Good luck in your testing of the Hornady's ,seems good bullets are hard to come by or $$$$.

 

I'd be curious of the Chrono stat's if you get some .

[seasprite]

Just don't do  like I did last weekend in testing the Barnes LE bullets . I moved them to the back seat & they were in a slip top case ( which I normally don't use ) & I thought I had them secure , but first braking & it was " 52 pick up " ,so I weighed them all , thinking I would see the changes in weight of the powder charges . Not so , the charges were too close & I have no Idea what was what & my ES &SD & Vol. showed this .

 

I have some of the 168 gr, Hornady match bullets & have used them & they printed pretty good @ 200 yards. , I may have a photo of the target some where. Good luck in your testing of the Hornady's ,seems good bullets are hard to come by or $$$$.

 

I'd be curious of the Chrono stat's if you get some .

 

Sharpies are your friend brother, I mark all my brass with either charge weights or length or what ever I,m trying to do so I don't ever get them mixed up. The markings come mostly off when I tumble the shot brass then I'll use some 0000 steel wool to remove the rest, doesn't hurt the brass any. I'll take the cronny next time and get some numbers and see how constant the numbers are. 

[seasprite]

Made it to the range after church today and took the chrony with me so I have some numbers to go with the target pics even though I only got one read on the .645" bullets. 

 

Here is the chrony results: conditions sunny and 75* no wind all shots at 100 yards

 

.633" length bullets seated to 2.176"

ES 39

SD 15

AVG 2550

 

1.) 2547

2.) 2561

3.) 2526

4.) 2554

5.) 2565

 

.645" bullets seated to 2.188"

ONLY ONE READ HAD A PROBLEM

1.) 2561

 

.660" length bullets seated to 2.203"

ES 23

SD 12

AVG 2561

 

1.) 2561

2.) 2576

3.) 2577

4.) 2554

5.) 2554

 

Now for the target pics

 

So by me varying my seating depth by bullet length seems to have somewhat stabilized the load and point of impact shift seems to be a lot less now than on last weeks targets. So now that one question has been answered now theirs another the .660" bullets seemed to group and put up more consistent numbers across the chronograph.

 

So I think I might try seating the .633" and .645" bullets a little deeper to get better groups and more consistent numbers on the chrony I'm only talking about .002-.003 deeper what do you guys think? 

 

[survivalshop]

Go for it & see how they group .

[Justintoxicated]

DSCF0427.JPG

 

DSCF0428.JPG

 

That gives me around .027" difference which to me seems pretty excessive, as far as the seating plug goes I don't think I'm having any issues there because it leaves a slight ring around the ogive at same place on every round that I seat.  

damn that's strange.  Have you tried the sinclair comparator?

[seasprite]

damn that's strange.  Have you tried the sinclair comparator?

 

No just the Hornady, but I thought about buying another Hornady to see if its the barring surface thats longer or just the boat tail. Just out of curiosity is their a difference between the Sinclair and Hornady?  

[seasprite]

Go for it & see how they group .

 

Guess what I did today and I had a few issues but all in all I have to say. <thumbsup>  <thumbsup>    :banana:  :banana:

 

First lets talk issues today it was raining plus I had an scope issue on top of that. The scope issue was the mount came loose so I fixed that and took 3 shots with some Winchester 180 gr. soft points and they were way high for that heavy of a bullet and normally they shoot way low on the target so I new I lost my zero. So now I,m out of sight in ammo and only have my test rounds left so I took a WAG at the settings and fired 1 shot with the 2.182" ammo and hit high right in the 8 ring. I wanted the rounds to hit a little lower so I made 1 more adjustment to the scope and started testing.

 

So the first group only has 4 rounds because of the scope issue but was still able to get great results.

 

Conditions for the day: 68*, overcast, raining  so no chronograph today.

 

Target pic

 

 

The 3 shots together on the first target measured at .437" and over all .945" so I should have my sub moa load back.

 

So the lessened learned through all this is my rifle likes consistent pressure as in the amount the bullet is seated in the case vs. the amount of jump it has to make to the lands and I'll be measuring the length of my bullets for now on.