Extreme spread problems

hi all

I'm having a real difficulty sorting my extreme spread on my 300 rum. I'm using Redding dies on a hornady press and a charge master 1500. I full length resize, I'm not 100% sure on where I should start to improve things

Cheers
Lucas

Tagging in

How much spread are we talking and what brand of chronograph are you using? Also, what kind of powder/bullet/primer and barrel?

Es is usually a reloading issue, or components that do not work well together in your rifle. Can be as simple as a primer change.

Get a better scale. I have found autochargers can vary by .2-.3 grains easily. RCBS & Hornady both.
Try throwing .2gr less than final.load, and transfer to a good beam or digital scale. Then trickle up to the individual kernel of powder.

Also, may not be an optimal charge.

But, if you are only shooting to 500-600, a 30ES won't be very noticeable.

I'm running 230 Berger hybrid targets, 91.5grs of adi 2217 with fed large rifle magnum match primers. My groups are the best I've ever shot 3/8" at 100 yards. As for the chrony I just borrow a local shop one so maybe that's where I start.

Cheers
Lucas

Is give Redding dies just normal non bushing set? As mentioned earlier throw under and do final charge on better resolution scale. I run a chargemaster also but then trickle up. From what I have seen crazy ES has two very common culprits. Chargeweights not being accurate to each other and/or running to much neck tension. There are few others but these are my first on the list of things to check.

Also check bullet weight. Sort a few out that matches and see if that helps

Awesome thanks guys. Does anyone have any recommendations for scales and Chronys?

A&D Fx120i and either magnetospeed v3 or labradar. Budgets may vary lol

Thanks for the info jimbo... one other question - what kind of brass are you using, how many firings have they had, and what are the steps you are using for brass prep? Okay, that was more like three questions.

The Magnetospeed and Labradar are the preferred chronograph these days.

Great point. I anneal on every firing FL bushing size and mandrel necks last. Them RUMs can work some brass so if u aren't on an annealing schedule u might want to add that to your calendar lol

The biggest thing I have found to tighten up ES is with finding the powder "node". Primers can also tighten up velocities, as stated above. I have experienced primers helping fist hand. My custom .308 Norma had extreme spreads in the 30-40fps area for 5 shots. I switched from Winchester magnum primers to Federal 215s and my ES shrunk to 12-19 FPS after testing multiple times with 5 shots each.

As others said though, you have to have an accurate way of measuring powder. I use a Bald Eagle digital scale. I'm not sure if they make them anymore or not. We also have a RCBS beam scale, my Dad prefers it. Both scales will read the same powder charge equally. Meaning if the Bald Eagle measures 45.0 grains, so does the RCBS. The RCBS Charge Masters or any other powder measure works great to dump the majority of the powder, but I highly recommend trickling the last few tenths on a scale and double checking it.

I would get a beam scale, preferably an RCBS, and use that to trickle with after throwing the charges on your Charge Master. When you have that, then I would work on finding the powder node. Do this by loading one round each in 0.2gr increments from a few grains under max, up to max. This will show what charge weights produce similar velocities. For example, 90.0 grains goes 3010, 90.2 does 3020, and 90.4 does 3012. If you load 5 up at 90.2, using an accurate scale, I will bet the ES will be under 30fps, probably closer to 20 or under with the right primer. This is just a pretend example, but that's what you're looking for when finding a powder node.

I use a MagnetoSpeed sporter, they're around $160. It's far far better than the old Pro Chrony we use to have. It does affect group sizes and point of impact on my rifles, but I just focus on finding a powder node and then I shoot groups to find the sweet spot for seating depth. Once I find a good shooting load, I'll retest it over the chrono to verify it. This is the method we have been using lately, and it works great and is the most affective and efficient method I have tried.

I suspect annealling may be needed