Chasing Accuracy Twice - 6.5 PRC Reloading Log

[he_lives]

I started reloading back in 2012 with a Lee Challenger reloading kit, relying on what I could learn from books and whatever was posted on forums at the time. Lots of trial and error. I spent the first few years throwing powder charges with the Lee plastic powder measure, trickling powder by hand hunched over the included beam scale, and loading ammo into spent brass I had collected. It was time consuming, and didn’t yield the best ammo, but it was good enough to fill my tags and I haven’t hunted with commercial ammo since.

I started reloading when I had more time than money, originally just wanting ammo to go hunt with for cheaper than I could buy it. Now, raising a young family has shifted my focus to prioritizing time a bit more than doing things cheaply and I’ve upgraded to better equipment.

I also wanted to point out that I fully agree with the “painless load development” concept that Form has posted and see how it can quickly get a rifle shooting accurately enough for any reasonable hunting scenario. I reload as a hobby. I enjoy most aspects of it and like to tinker with new loads and rifle combinations. These days, it’s easier to carve out a couple hours of range time, versus the time it requires me travel to hunt. Developing a load is something I enjoy doing, even if it could be done quicker with the painless method. If you’re at a place in life where you can be away from home hunting, absolutely do the painless method and don’t waste that time at the range or in the reloading room

To the point of enjoying tinkering with my setups, I’m currently pulling a 300 wsm barrel off a Tikka action to try out a 6.5 PRC barrel I bought off a member here. Nothing wrong with the 300 wsm, and nothing really to be gained by switching calibers. It shoots repeatable 1.1 to 1.25-moa groups with 168-eldm and 185-juggernauts. I just feel like seeing was the rifle is like in 6.5 PRC.

Shortly after buying the Tikka 6.5 PRC barrel, an Origin carbon Proof 6.5 PRC barrel fell into my lap at a price I couldn’t say no to. I had no plans to put together two 6.5 PRC rifles, but I’m going to play around with it as well.

Since I am going to work through load development on two different rifles, I figured I would start a reloading log to show my process. It may provide a couple tips to new reloaders, and I’m sure anyone that may read this could provide some critiques to my current process.

Here are the rifles I’ll be working with:

Tikka:

• Factory 6.5 PRC 1:8 Twist Barrel, cut to 20" and threaded 1/2" with adapter to 5/8". Purchased from a member here with 50-rounds on the barrel. Unsure who did the barrel work or where the adapter was made/ purchased from.
• SWFA 3-15 scope in Sportsmatch Rings
• DDC Enticer LTi direct thread.
• Stock except for Tikka vertical grip and Limbsaver Airtech recoil pad.
• The unloaded rifle with suppressor weighs 8.4-pounds and is ~ 48-inches total length

Note: Photo is with 20" 300 wsm barrel still installed, but same final form.





Solus spare parts rifle:

I had originally planned to install the Proof barrel on a long action and run the bullets long. After measuring the COAL for several bullets at the lands, it looks like a short action is best suited to this barrel.

• 24" Proof 6.5 PRC with 1:7.5 Twist. Area 419 Hellfire Brake
• Solus Lightweight Short Action
• Trijicon Tenmile 3-18 in Seekins Precision rings
• XLR Magnesium Chassis with Magpul MOE stock and 3D printed grip, thumbrest, and bag rider.
• The unloaded rifle weights 9.2-pounds and is ~44-inches with the stock in the position that fits me.

I will update this as I work through the load development process.

 

[streamerfish]

Cool, looking forward to seeing how it goes....

I am pretty much a "painless" reloader from a efficiency of the actual reloading steps, or lack there of. But, I like to tinker with load development as well, And I will be doing similar with my 6.5 creed.

 

[he_lives]

Step 1

These two rifles are not good examples of my normal first step as the barrels were both purchased from the classifieds.

Typically, when I am trying to pick out a barrel, cartridge, and bullet combinations, I build a spreadsheet to organize the different options. Here are my steps:

• Select a bullet (or several) that I want to hunt with
• Use GRT to play with barrel length and powder combinations that meet my needs. I'm not trying to be perfect with exact measurements here, but I'm looking for bullet & powder combos that provide burnt powder ratios close to 100% and case fill somewhere in the 90% range. I also don't prefer to operate at the ragged edge of being over pressure.
• I take the GRT estimate and plug that into a ballistic calculator. I hunt deer every year at EL.1400' and most my elk hunting is between EL. 5000' and EL. 7500'. I limit my shots to 600-yards, hopefully less. I'll set conservative "minimum" expansion velocity for deer (typically 1900-fps) and a little higher "desired" velocity for elk (typically 2000-fps).
• The last two bullet points are iterative. I will go back and forth on several bullet/powder combos and vary the barrel length until I find the shortest barrel with the lowest recoil that meets my velocity goals at 600-yards.
• Once I have a few bullet/powder combinations that I think will produce the desired velocities at reasonable pressures, I will order a barrel.

Here is a simplified example of the spreadsheet I built to organize potential combinations:



As mentioned, I bought these barrels first and did the research second this time. For a better example, here's my spreadsheet playing with bullet/powder combinations in advance of ordering a 280ai barrel last fall:



The highlighted rows are combinations I think look promising.

 

[he_lives]

Step 2

Once the barrel is available, I find where the bullets I have selected touch the lands.

When I first started, I would cut a slot in a spare case to relieve some neck tension. I'd place the bullet in the case, chamber the round, and measure the cartridge after the bullet seated itself against the lands. This isn't repeatable, but can get you close if this is all you have.

I next moved to the Hornady OAL gauge with modified cases. I will still use this for rifles where I don't want to pull the barrel.

The most repeatable method I've found is outlined in this article: LINK

In summary, load a bullet seated long. With the barrel removed, place it in the chamber with light tapping. Then bump the bullet shorter and shorter until it doesn't "stick" in the lands. I use this method when its feasible to have the barrel off.

Tools Used:

• Reloading Press
• Seating Die
• Collet Bullet Puller / Inertia Bullet Puller
• Bullet Comparator. I use the Hornady set. Link for Reference
• Dial Calipers. Any decent quality set will work. I use the Mitutoyo 505 calipers
• Optional - OAL Gauge. I use the Hornady set. Link for Reference
• Optional - Modified Case for 6.5 PRC. See above link.

Since I never know what bullets I will end up using, I like to measure the distance to the lands on several of the bullet options I have on hand before the barrel is installed. Here are the results from these two barrels:



The internal length of the Tikka mag is ~3.3" so no issues with COAL on the Tikka.

I mentioned earlier that I had planned to put the Proof barrel on a long action and seat bullets long. Currently, I'm most interested in a load using the new 153 TMK bullets and plan to work on them first. I had assumed, incorrectly, that I'd need more mag length than a short action mag would allow. You can see from my measurements that the bullet touches the lands with a COAL that fits short action mag length.

If the 153 TMK bullets don't pan out, I'll likely move to a 143/147 Hornady. My measurements show I can fit those at mag length with a reasonable jump.

 

[he_lives]

This isn't necessarily a load development step, but part of the overall process that might be helpful to someone just starting out.

Now that measurements have been measured for potential bullets, the barrels are installed with internal wrenches and torqued to 75 ft-lbs.

I need to make some rounds to sight in, test for any issues, and typically keep a few for warm up rounds.

I have new ADG brass that I am going to use in the Proof barrel. The Tikka will use 1x fired Norma brass.

For the new ADG brass, I simply dry lube the necks with Imperial Dry Neck Lube and run them through a PMA Tool neck expanding mandrel. Then chamfer and debur the case mouth.

The Norma brass was fired in a different rifle. I didn't clean the brass. I just lube with Imperial Sizing Wax, re-size full length based on standard die settings, wipe off the wax, chamfer and debur the case mouths.






With the price of components these days, I go really cheap with these sight in rounds. For both rifles, I'm using 59 grains of pull down Mag Pro powder, a mixed lot of pulled 140 ELD-m bullets, and primers I punched out of some other reloads I broke down. They're a bit ugly, but will work for getting me on paper.







Hoping to get to the range to sight these rifles in soon.

 

[hunterjrg]

Nice write up. I find interesting to see how others load compared to mine

 

[he_lives]

I was able to get to the range yesterday to sight in and function check the rifles.

Had good conditions. Low 50’s, low/no wind, clear.



I shot 5 rounds in each rifle to check function and sight in the new barrels.

I then shot 10-shot 100 yard groups with each rifle, allowing 45-60 seconds between shots.

I’m not planning to do anything with these loads using pull down components, but I record them anyway.

Here’s how they shot:



24” Proof - Avg: 2724-fps, ES: 87-fps, SD: 28.2-fps, 10-shot group: 1.5-moa

20” Tikka - Avg: 2556-fps, ES: 45-fps, SD: 13.3-fps, 10-shot group: 0.6-moa

These turned out to be about at 6.5cm velocities, but worked well enough for sight in and to get a few rounds on the barrel.

I mentioned earlier that the tikka barrel was used, with an unknown round count believed to be less than 50. Since it’s low, I’m not going to guess at what the previous round count might be, and will just track the rounds I’ve shot.

Current round count on both barrels: 15

 

[Odd1out]

What primers and coal were you using for the tikka load?

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