Is it really necessary to clean the primer pocket everytime?

[Unclenick]

Jimro.

I asked because the retired Marine Scout/Sniper and SWAT sniper who taught the class I took at Gunsite had us clean every 10 rounds on the fixed ranges, no matter where we were in the class schedule, and excepting only the field trip to a long range position to try a sniper+spotter team exercises and the shoot-off competition at the end. So it may be a different schedule. Obviously a combat situation could change anyone's schedule.

I don't know about the cleaning equipment, either. I can comment that the Marine Scout/Snipers who used to help coach Mid Tompkins's Long Range Firing School at Camp Perry before the war in Iraq started, were interested in the equipment civilians brought with them. My firing point coach expressed interest in acquiring a wind speed meter like the one I had and we emailed about it a couple of times afterward. So the Marines may be more flexible in what they allow their guys to pick up on or improvise with. I don't know what official policy is.

If you look at Gunzilla's web site, they discuss a lot of regular troops substituting their product for the issue CLP and claim a 75% reduction in stoppages resulted because their product doesn't attract fine dust. So I suppose it's hard to know exactly what the deal with the M24's really is if you don't know what the guys are actually using. Krieger makes barrels with Boots Obermeyer's 5R profile available in some barrels, but he says:

"The Internet is full of information describing perceived benefits to the 5-R™ rifling over conventional styles, but most of this is comparing "apples to oranges" as they are usually comparing one manufacturer's "non 5-R™" to a different manufacturer's "5-R™" barrels. We have honestly seen no significant differences in accuracy or performance between the two styles of rifling when comparing our barrels."

So, it seems like the steel would be what matters in regard to life expectancy. Unless, of course, the Marine cleaning is better and we're back to Humpy's carbon theory.


TxGunNut,

I think you just fire 20 to 100 rounds of each (whatever is needed to get about 10 times your scale resolution accumulated) and then use a standard screwdriver-like cleaning tool over a piece of paper to collect whatever is left in the pocket to weigh. This should average out a lot of mistakes.

[tobnpr]

I haven't even read the four pages of responses.
My answer is no. Never have, and I've never had an issue of any kind.

[WookieRookie]

I've been using a snake bedding made of walnut, and haven't had a problem getting anything stuck in the flash holes. It's really small. It also gets the pockets cleaner...not perfect, but no loose soot either.

[Jimro]

Unclenick,

It could be that the USMC rebarrels at 8k whether the rifle needs it or not. It was the USMC Pistol Shooting team that started the urban legend that a 1911 barrel needs replacing every 4k rounds. It turns out to justify a new barrel for the teams pistols every year the paperwork was written up to match the round count of a typical Pistol Shooting Season. Sometimes there is nothing so sacred as a budget justification...

Either way, the only other barrels I know of that routinely last past 10k are chrome lined FN SPR barrels, although I look forward to seeing some round counts on the S&W MP-15 series rifles, they have 5R rifling and melonite which may be better than chrome from a cost standpoint.

Jimro

[Unclenick]

That will be interesting to learn about.

The retired Air Force match team armorer I learned to build 1911's from said he figured about 25K for hardball barrels and wad guns shooting lead target loads would easily run way past twice that. They do get loose and need retightening from time to time, though, and checking that at 4K isn't a bad plan on a gun and frame that didn't start out machined to a match fit.

[hounddawg]

well you guys got me curious so I ordered a Lyman case care kit and it includes primer pocket reamers and cleaners. Will do a little testing myself on my 308 and 204 loads next week. Earlier today I loaded up 50 .204s 25 loaded with dry neck lube and 25 loaded without. I am going to shoot some 200 yard groups with each and see if the unlubed 25 gets more flyers than the lubed. Bullet Seating, powder charge etc are exactly the same and the were checked and adjusted as necessary to .001 or less bullet run out. Not very scientific but should give me a good idea of real world results.

Will do the same with cleaned and uncleaned primer pockets next week.

[oldmanFCSA]

Lube vs un-lubed, with graphite of course.

Questions:
Did you anneal the case necks every firing?
Did you neck turn brass necks to a consistent thickness?
Did you check inside diameter of necks for consistent bullet retension?
Did you trim and chamfer all identical lengths?
Did you seat the bullets to same depth?

Not to nit-pick you process, but these are items I must do every time I reload my 50BMG cases for competitions at 1000 yards.
I lube with dry graphite, and set ID of neck to 0.002" diameter retension.

This should be a good test anyway !!! HAVE FUN - BE SAFE !!!!!!!!!!!!!

[hounddawg]

Lube vs un-lubed, with graphite of course. - No I use talc, I prefer it over mica or graphite. The idea is so you have a consistent neck tension for every shot of course and I tried graphite but it was too messy for me. Some use mica with good results. I like the talc because it is free, bonus is it makes my rounds smell nice and does the job

Questions:
Did you anneal the case necks every firing? Cases have been fired twice, I anneal after the 4th
Did you neck turn brass necks to a consistent thickness? Fired cases which were inside neck reamed before neck sizing in a collet die
Did you check inside diameter of necks for consistent bullet retension?since all were fire formed cases whose necks were reamed to the exact same inside dimension I would say yes
Did you trim and chamfer all identical lengths? Yes
Did you seat the bullets to same depth? Yes, each was checked for bullet seating depth and runout

Not to nit-pick you process, but these are items I must do every time I reload my 50BMG cases for competitions at 1000 yards.
I lube with dry graphite, and set ID of neck to 0.002" diameter retension.

This should be a good test anyway !!! HAVE FUN - BE SAFE !!!!!!!!!!!!!

Just out of curiosity what competition do you use a 50BMG in, never heard of anyone shooting one in open F and certainly not in Palma.

[Unclenick]

Hounddawg,

Note that inside neck reaming will uniform the size of the hole and remove any donut at the neck/wall junction, but unless you had some way to constrain the outside of the neck coaxial with it (such as in the old Lee Manufacturing Zero Error target version of the Lee Loader), it will tend to remove metal equally around the inside of the neck. That will correct an overly thick neck after forming a case from a wider mouth parent, but it can actually exaggerate rather than eliminate difference in neck wall thickness. It normally takes an outside neck turner to improve that.

The Lee Collet die prevents the donut from ever forming in the first place, BTW, so you don't usually need to inside ream using it.

[hounddawg]

Just double checked a couple after reading your post Nick because it does make sense and I can follow the logic but according to my measurements the case necks are completely uniform in every way. They are an exact .013 thickness. Inside miking the cases shows a constant .201 and outside they are .227. Using a ball mike shows me exactly what the measurement do which is a .013 wall.

Checked 5 random cases that are ready for powder and all gave me the same readings measuring each neck in five or six spots. I am using the reamers made for fired cases and after the reaming the case the first time all I normally ever get after that is a bit of carbon.

These are the same cases and gun that gave me the .2 5 shot groups so I really think they are pretty uniform. The real test will be groups from the 308 at 200 and 300.

Anyway I bought the tool because I was tired of twisting the case for chamfering, the pocket uniformer was just bonus.

The real test will be if

[oldmanFCSA]

Today, 02:29 PM #83
hounddawg
Senior Member


Join Date: March 1, 2009
Posts: 287

Just out of curiosity what competition do you use a 50BMG in, never heard of anyone shooting one in open F and certainly not in Palma.
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Last edited by hounddawg; Today at 02:43 PM.

Fifty Caliber Shooters Association - we promote the Sporting use of the 50BMG cartridge. Please check our home page which shows many pictures of our competitions, which are held at 1000 yards, regardless of weather conditions as long as targets stay up. www.fcsa.org

So far my smallest group has been 5-shots under 5 inches center-to-center at 1000 yards. The record is 5-shots under 2" center-to-center at 1000 yards. All groups must be in FCSA Matches to be recorded for posterity.

[FrankenMauser]

2,000 S&B, 1,500 Fiocchi, and 1,000 Magtech Small Pistol primers showed up today. If I can find enough clean brass for a pseudo-scientific test, I'll run it.

Otherwise, the comparison will be mostly for my own benefit.
(Also on hand: Rem, Win, CCI, Federal.)

[Salmoneye]

If I do not clean the primer pockets, I sometimes find primers that are slightly flattened due to not being able to bottom out in the hole...

[Unclenick]

Salmoneye,

You may also be seeing the web of the case pushing back under pressure (happens a little at each firing) and making the pocket shallower. A a depth uniforming tool will fix that. If you have primers on a stack of residue, they may be slightly cushioned by it. That can result in ignition delays. These are often too short for the shooter to notice (milliseconds to 10's of milliseconds), but can be long enough for


Hounddawg,

Did you check the cases before reaming? It's always possible they were uniform to start with, and that would work out fine with inside reaming. Lapua and Norma brass are often that good throughout a whole lot. With Winchester, at the other extreme, I've had .308 cases with as much as 0.008" TIR in neck thickness (0.004" difference from one side to the next).

See if you can find a bad case you haven't reamed yet (maybe a range foundling, if not your own) see what happens when you ream it? If it comes out uniform, I'd like to know whose reamer you are using so I can find out how it is correcting the problem. There is some tendency of a thinner neck wall to deflect off the reamer and not let it dig in as firmly. Perhaps a method of better exploiting that principle has been worked out? The whole reason outside neck turning tools were invented was to address the wall uniformity they couldn't get from inside neck reaming, but perhaps someone has come up with another solution.

The old Zero Error Lee tool reamed the neck while it was inside the neck sizing portion of the tool, which extended up to serve as a journal for the reamer and seating tools. In that way it forced the reamer to remain concentric with the outside of the neck as it cut. It kept neck walls pretty uniform, and for .308 and .30-06, at least, also aimed at .013" wall thickness.

[Salmoneye]

You may also be seeing the web of the case pushing back under pressure (happens a little at each firing) and making the pocket shallower.

Thanks for that, but the flat primer after seating seems to go away when I am diligent about cleaning the pocket...

I have always been worried about brass flow, and seldom use cases more than 5 loadings...

[hounddawg]

Well Nick I can say for sure I have examined cases under a bright light and a magnifying glass after the first reaming and saw b shiny spots on the inside of the neck and brass shavings on the reamer. Way I look at it, the way my groups are developing I am not going to mess with what I am doing too much, I will uniform the primer pockets on all my cases, and may even start cleaning them. It's about the only thing left and who knows it may give me that little bit extra at 800 or stop a flyer.

what I need to do is work on my wind reading and shot timing more than my reloading, I think I am loading the most accurate rounds I can but that nut behind the trigger can always use a bit of improvement

[hounddawg]

gonna bump this because yesterday I chrono'ed some loads in my 260 with and without primer pocket cleaning.

I took 50 260 Remington once fired Lapua brass cases. Half with primer pockets were reamed with a Lyman primer pocket reamer and half were not. I loaded 120 grain SMK's over 36.0 grains of Varget. Each powder charge was individually weighed on a mechanical scale then checked on my electronic. 5 round groups , with a 5 min cooldown between groups. Barrel was cleaned before each set.

Reamed - High velocity was 2783 low was 2749 SD of the 25 rounds was 9.35

Non reamed - high 2793, low 2732 SD of 13.8

For whatever it is worth I will be cleaning the pockets on all my BR and LR rounds from now on. In my mind anything that gives me more consistent velocities or even just a bit more confidence is worth the extra half hour of case prep. maybe I am just a superstitious bastard, but to me if I even think it works that is all the reason I need.

[Unclenick]

Thanks for the follow-up.

I'm not surprised that reaming primer pockets helps because even in new bulk purchased cases I can feel some case-to-case variation in seating effort. You have to get them uniform to prevent that resulting in a difference in force applied to compress the priming mix between the cup and anvil. As one author pointed out, primers are analog and not digital. You need to expose them to the same forces every time to maximize uniform ignition time. It's the reason I run even uncrimped cases through my Dillon swager before I first reload them. I've also used the Wilson profile cutter for this, which does a cleaner job, but which takes ten times the work to accomplish.

The other tool, the primer pocket uniforming cutter that gets the depths of the pockets the same and that is often used for cleaning to keep the pocket depth constant, is another factor in keeping primer seating forces constant. That's because the mechanical advantage of many primer seating tools changes significantly as the primer goes deeper in. So if your primers bottom out at different depths, the same feel represents different forces on them. So that's another argument for cleaning them, but only if you also keep them equally deep.

[hounddawg]

Well Unclenick I figure it is like lubing case necks before seating, it is only worthwhile if you are going for long range like F class or benchrest, varmint shooters might benefit. For the average shooter who is happy with minute of deer or shooting at 100 yards it would pretty much be a waste of time. Run some ballistics at realistic hunting distance and you will see what I mean. I doubt it would be worthwhile for pistol ammo since I can't see where 50 or 75 FPS difference between shots is going to have much of a effect at 25 yards or less.

[MEATSAW]

From prepping once-fired brass in 40S&W it is apparent that Remington primers (or whatever is used in UMC) leave considerable residue in the pocket. I just did a batch of 500 rounds and every piece of de-primed brass I inspected the primer pocket: 90% of the ones I felt needed to be cleaned out where Remingtons. I have been using Fed-100s and find them to be excellent in all regards.

[hounddawg]

interesting observation Meatsaw. I use CCI's in my handguns and while the primer pockets certainly have some residue it is not what I would call excessive.

[oldmanFCSA]

While consideration to proper Primer and Powder selection can and will make a difference to cleanliness of the insides of a case after firing, I feel proper selection of Primer and Powder is whatever combination results in the best accuracy, regardless of residue.

Then as a diligent reloader, proper preparation of the fired cases was my responsibility to create and maintain the techniques required to produce Quality Ammunition each and every time. (I understand some of you just want "blaster" ammo, but when such ammo is selected to shoot a game animal or a competition where large fees may have been paid, don't ruin it with a cheap reload with improper loading techniques.)

I clean each and every case, whether by hand or by tumbling. I have found a method that cleans in 1 step, what I used to do in 3 - clean primer pockets, tumble cases, check flash holes for media. That method is Stainless Steel Pins. It does all 3 with no extra work than any other process.

So why not use it to produce Quality Ammunition each and every time?
Before you try to discredit the process, try it. It will exceed your expectations, if you leave your mind open to new methods.

[m&p45acp10+1]

For handgun I do not clean the primer pockets, and with my shooting no one would ever be able to tell a differance anyway.

Now with rifle rounds I do not clean the primer pockets purpousefully. I do deburr the flash holes every time. I will use a primer pocket reamer to make sure none are too tight, or loose for seating the primers. I get exelent groups with my rifles anyway, even if I do not clean the primer pockets, or deburr the flash holes. I just do so as a feel good measure.

[hounddawg]

Considering that the stainless steel pin kits run from 250 to over 800 dollars I considering that a pot of boiling water with a little some detergent will get the cases just as clean, I see no reason to buy one. The stainless pins will polish the cases and make them prettier but you won't get any better groups than a clean unshiny case will. I can have clean without being polishing

[oldmanFCSA]

Interesting how you factor in cost of SS Pin process with absolute highest cost of professional equipment, when $50 of pins and existing tumblers will work, as opposed to working with heating up water to a boil with an expensive stove, dealing with the danger of boiling water, and HOT brass.

Be SAFE, Have FUN, something you're not doing!