300 wsm load development

[mpriest]

On 12/22/2022 at 10:24 AM, L Cazador said:

Recently checked bullet base to ogive measurement on a box of Hornady ELDX (sample of 10 bullets) had as much as .010" difference while Berger only .002"(sample of ten bullets). While H4350 worked best for me with 168 grain bullets, H1000 and RL26 both temp stable worked best with 200 grain plus bullets.

After reading this I was curious about my bullets. I’ve been gathering reloading supplies where I can for a 28 Nosler build I have but haven’t been able to shoot yet. I can’t find primers. I bought 175 grain ELD-X and 180 grain VLD hunting to try. I measured from Ogive to the base of the bullet using 10 random bullets from the same boxes. I found the opposite with my ELD X bullets being more consistent. I wonder if the thickness of the jacket on the base of the bullet in my lot might be inconsistent. Guess I won’t know for sure until I actually load some rounds. Used Sinclair comparator with a Mitutoyo caliper. Heres my measurements for what it’s worth. I also measured my new brass out of curiosity. 

[MMACFIVE]

13 hours ago, 452b264 said:

Berger will recommend you start .15 off the lands and work back at .5 thousandths. 

If seating depth didnt matter then why can my 300 win go from this to an 1.5 inches?

 

 

You must of missed the part about Hornady bullets. Which is the OPs choice. 

[452b264]

My 6,5 PRC with 143 gr. ELDX is .55 off the lands thats where it shoots the best.

[L Cazador]

9 hours ago, 452b264 said:

My 6,5 PRC with 143 gr. ELDX is .55 off the lands thats where it shoots the best.

You state .55 off the lands, that means 550 thousands off the lands?? I presume you mean .055" or 55 thousands off the lands?? How do find where your lands are?

[452b264]

18 minutes ago, L Cazador said:

You state .55 off the lands, that means 550 thousands off the lands?? I presume you mean .055" or 55 thousands off the lands?? How do find where your lands are?

https://www.amazon.com/Hornady-C1000-Lock-N-Load-Length-Straight/dp/B000PD01SI

[L Cazador]

7 minutes ago, 452b264 said:

https://www.amazon.com/Hornady-C1000-Lock-N-Load-Length-Straight/dp/B000PD01SI

That tool measures to your bore diameter and the tool your'e measuring with the comparator is not a true representation of your bore diameter. What caliber are you loading?

[BeardWonder62]

27 minutes ago, L Cazador said:

You state .55 of the lands, that means 550 thousands of the lands?? I presume you mean .055" or 55 thousands of the lands?? How do find where your lands are?

[BeardWonder62]

So would a pre made case insert be much different then once fired case from your barrel case? 

[L Cazador]

12 hours ago, BeardWonder62 said:

So would a pre made case insert be much different then once fired case from your barrel case? 

Of course much different but that pre made case is not the issue. The issue is one tool measures to the lands diameter and the other tool (bullet comparator) uses an arbitrary measurement! That's why you use your own case fired in your rifle and either use the touch method or jam method. Go to " you tube" and watch Alex Wheelers" touch method for finding lands or Erik Cortinas "jam" method. Both methods work equally well. I've been using the jump method for more than 50 years now. Just remember to apply die wax or some lube on the bullet so the measurement isn't distorted. 

[Mike S]

On 12/22/2022 at 8:42 AM, L Cazador said:

Generally, magazine length can be .100-200" off. Strip the bolt and find "bullet touch" first then calculate measurement to lands. 20-30 off is only important from a liability standpoint for Hornady and for you its a safety issue. Sticking a bullet in the lands is very dangerous. Seating depth is however very important as it can influence extreme spreads, velocity, point of impact, and group size!!!By the way that load above is a pretty hot load. Sierra book shows 59 grains of H4350 as max. with an average velocity of 2800! Also the recommended powders are H1000 and Retumbo for the 200 grain bullet. H4350 is faster burning than Retumbo and H1000. Use with caution.

What is your definition of "sticking a bullet in the lands"? While I would not use it for hunting loads, seating into the lands is pretty common practice for many forms of competitive target shooting...

[MMACFIVE]

11 hours ago, L Cazador said:

Of course much different but that pre made case is not the issue. The issue is one tool measures to the lands diameter and the other tool (bullet comparator) uses an arbitrary measurement! That's why you use your own case fired in your rifle and either use the touch method or jump method. Go to " you tube" and watch Alex Wheelers" touch method for finding lands or Erik Cortinas "jump" method. Both methods work equally well. I've been using the jump method for more than 50 years now. Just remember to apply die wax or some lube on the bullet so the measurement isn't distorted. 

The  Hornady OAL gauge may have some faults, as do all the other methods, but it is repeatable and convenient. 
 

I use it almost exclusively now and am very happy with it. It gives me a datum to work with. 

[L Cazador]

1 hour ago, Mike S said:

What is your definition of "sticking a bullet in the lands"? While I would not use it for hunting loads, seating into the lands is pretty common practice for many forms of competitive target shooting...

I'm a target shooter and while yes I may be .003 .006" into the lands that is not going stick a bullet in the rifleing but most of my target rifles shoot at touch or up to .015" off. Sticking a bullet can be neck tension specific. Ie; more neck tension can prevent a stuck bullet.  But I wouldn't advise any novice reloader to seat bullets in the lands unless they have proper measuring tools. Sticking a bullet refers to a bullet being pulled out of the case and left in the bore. I measure seating depth and headspace with a barrel stub that's a true representation of my chamber and bore. The pics show the difference between the inside diameter .3070" of a 30 cal. bore groove and the inside diameter .2955" of a Hornady bullet comparator. The bullet comparator provides a reference point to work from but it is not a true measure to the lands. You work .020" to .030" off that measurement to start. Most reloaders do not have barrel stubs but they can measure with suitable accuracy distance to lands with a bullet seating gauge such as the Hornady. The two tools are not one and the same, the bullet comparator and the bullet seating gauge. Most SAMMI chambers have generous dimensions that will never be reached by a cartridge that fits in a magazine. So unless you load single shot, make a dummy that will fit your magazine and work your way back away from that measurement in increments of .010". I recently did a stock 300 PRC and had to start from .035" off, ( magazine max length) found the best load at .055" off. Worked at .010" off for each group. The final group size of .450" with an ES of 15 at a hundred was the proof I needed that the starting length of .035" wasn't the best seating depth!

[Mike S]

OK, I understand what you were referring to now. While I agree that leaving a bullet stuck in the rifle when ejecting a loaded round is inconvenient, I can't classify it as "very dangerous". It is not like you can follow up with a live round. 

As for your caliper measurements, it is problematic to measure the I.D. like that. Not the right tool for the job. I would expect the bore diameter (which the comparator insert should be) to be .300. The .2955 is close. The groove diameter should be .308. the comparator is designed to measure the bore diameter (top of lands), it is not just a reference point.