Question about .308" Sierra bullets.

[ddjchemist]

I use Sierra .308" 168gr and 155gr MK HPBT bullets, and I am getting great results from them. However, I am not happy about the difference between batches. I buy them in box of 500 and I find difference between batches 0.015-0.020" (OGIVE). If you use the same bullets, did you notice this? I am wondering if they always had this differences between batches, or it is something related to lower QC in the post-COVID years?

Dan from Seattle

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[drstrangelove]

lower QC in the post-COVID years… throughout most industries.

 

[ddjchemist]

lower QC in the post-COVID years… throughout most industries.

I have a feeling there is no a QC anywhere these days. Our lab purchased a $600K analytical instrument (Mass Spectrometer). The instrument was installed at the end of October, and it is still not working. Every week or so some major part fails and they have to keep replacing parts. At this point, they replaced 1/3 of all major parts.

 

[kmk1012]

I have a feeling there is no a QC anywhere these days. Our lab purchased a $600K analytical instrument (Mass Spectrometer). The instrument was installed at the end of October, and it is still not working. Every week or so some major part fails and they have to keep replacing parts. At this point, they replaced 1/3 of all major parts.

At least you can get stuff, my automatic power transfer switchgear for our 175kw gen failed in a lightning storm and the city lost water for a couple hours. Boil water notice and the whole works, been waiting for four months for new stuff with at least three more months to go.

 

[ddjchemist]

At least you can get stuff, my automatic power transfer switchgear for our 175kw gen failed in a lightning storm and the city lost water for a couple hours. Boil water notice and the whole works, been waiting for four months for new stuff with at least three more months to go.

Sorry to hear that. We live in crazy times called "era of junk products."

 

[kmk1012]

Sorry to hear that. We live in crazy times called "era of junk products."

Junk products and junk employees. I'm not old but am old enough to remember when made in America was a good thing.

 

[ddjchemist]

Junk products and junk employees. I'm not old but am old enough to remember when made in America was a good thing.

I am in my early 50s and grew up in Europe. I remember when I was a child, German cars plus Volvo were symbols of reliability and could drive over 500,000 miles. Now look at German cars (plus Volvo). They put tons of plastic in the engine bay. After warranty, they are nothing more than endless money pit (my ex wife had a new Audi Q that had electronic issue since day one, so on every long trips we drove my old 2003 Honda CRV that had close to 200K miles, but had engine and transmission that were bullet proof). That is why I would never buy any car made last 10 or so year. When I travel for work or oversea to visit family, I rent a car and it feels like driving a child toy, not a real machine. I apologize to those who might like new cars, but I got a free speech and like to express my opinion. You do not have to agree with it.

 

[P7M13]

Dan, are you measuring the bullets directly, or after they are seated?
I thought the same about CNC copper bullets, then measured the bullets only. The difference was the spring-back of the brass at seating.
There are usually lots to lot differences on brass and bullets. The machines are set up for production within production QA limits and then run. One lot to another will show differences, and I don't know how .020 on a bullet only would affect the BC and it's performance over 1km.

 

[Certaindeaf]

I use Sierra .308" 168gr and 155gr MK HPBT bullets, and I am getting great results from them. However, I am not happy about the difference between batches. I buy them in box of 500 and I find difference between batches 0.015-0.020" (OGIVE). If you use the same bullets, did you notice this? I am wondering if they always had this differences between batches, or it is something related to lower QC in the post-COVID years?

Dan from Seattle

By batches do mean lot #'s?
This is normal. This is why people strive to have all lot numbers.. primers, cases, powder, and bullets be the same, respectively, for minimum variation.

 

[Yarome]

By batches do mean lot #'s?
This is normal. This is why people strive to have all lot numbers.. primers, cases, powder, and bullets be the same, respectively, for minimum variation.

I've loaded .308 Sierra's for years. I don't know if it's really a QC issue, per se. It might could be, but I have to agree with @Certaindeaf. It's never been uncommon to see very slight variations between lots over the years I've used them. Not always between every order, but on occasion one batch or another... and why I always buy in quantity for "the foreseeable future". Once you dial a new "batch" in you're good to go for quite awhile.

I would imagine that mfg. tools, dies and molds need to be replaced from time to time and always chalked it up to that. I haven't bought any within the past year and a half or so though so can't speak to what you might have just received.

 

[Spitpatch]

Junk products and junk employees. I'm not old but am old enough to remember when made in America was a good thing.

Point of observation: what you may remember is that American products were better than crap from elsewhere ( not too hard to be better than crap).

"Elsewhere" has had a lot of time to catch up to our "little bit better than crap" standard that still holds today.

 

[Spitpatch]

As @Certaindeaf and @Yarome described, I would agree with their position of being unconcerned about what you have observed, and probably within normal manufacturing tolerances.

If I did find myself concerned about that variation in measurement, I would set out to prove or disprove it makes a difference on target. Such would be easy to accomplish toward a definitive answer in very short order.

 

[dangerranger60]

I have measured a lot of match grade bullets and found Sierra to have pretty good QC. A couple things I learned is that without the same bullet holding fixture I was not going to match the factory numbers. I was happy just getting bullets that matched each other. the other thing that I learned was that with boat tail bullets I had to measure off the tapered area as the bases are where the most variation is found . DR

 

[ddjchemist]

Dan, are you measuring the bullets directly, or after they are seated?
I thought the same about CNC copper bullets, then measured the bullets only. The difference was the spring-back of the brass at seating.
There are usually lots to lot differences on brass and bullets. The machines are set up for production within production QA limits and then run. One lot to another will show differences, and I don't know how .020 on a bullet only would affect the BC and it's performance over 1km.

I measure them first directly, and then I measure them using a bullet setting measurement tool. They always endue being about 0.020" different from lot to lot. You are correct, I am still getting the same accuracy results. I just adjust bullet seating in such a way to be 0.005" off the lands. I got lucky that I have two custom 308 Win rifles built by a same gunsmith and reamed with the same 168gr/175gr reamer, so my both rifles have the exact same cartridge specs. In fact, I only did load development for one of the rifles, and I have never had to do any load development for the other.

 

[whiskeybill]

Over many years, it's been my experience that serious shooters buy large quantities of the same lot number of bullets and brass. Some even get picky about the lot numbers of primers and powders. There will be less deviation in specs with components of the same lot numbers. Even in a particular lot number, there can be some minor differences. This is not a COVID related deal. Professional shooters like David Tubb have a deal with bullet manufacturers to get certain quantities of bullets and brass, all the same lot number. Many times it's a sponsorship thing.

"Batch" numbers, commonly called lot numbers, are just different production runs. Manufacturers will make so much of a certain bullet, then re-tool to do a run of a different type of bullet. When a production run is started, the factory has to re-set the tooling to get everything just right. This phase is generally where you end up with "Blems" or "Factory Seconds". The differences you are seeing between "batches" are to be expected.

 

[gmerkt]

It's never been uncommon to see very slight variations between lots over the years I've used them.

I can't say re. pre- or post-Covid. When I visited the Sierra Bullets factory in 2008, I was shown the storage area in the basement. Which was full of green 55 gal. barrels. This was their back stock of bullets. Because they aren't physically able to run all of their catalogue in production simultaneously. When they do a batch of X bullet, they do a lot. Some get packaged straight away. Others go into the green barrels for storage. In the meantime, the bullet making machines are tooled up to make some other product. When they run out of X bullet in the barrels (or fairly close to it), they schedule another run. Which involves new set-up. Which may explain minor differences. At least this was the situation in 2008 and of course subject to change. It seems like a business practice that may still be in effect.