The Creedmoor Forum

Check this out. Very interesting!

https://www.rollsizer.com/videos

I wanted to take a minute to wish you all a happy Easter. In these times of unrest and uncertainty it is so worthwhile to take a day to revel in the peace and promise of Jesus Christ. Regardless of your faith, or even lack there of, He is there for you with open arms. Today I reflect on my imperfections with humility and my forgiveness with great joy. With those thoughts in mind, I  pray for our nation and the wellbeing of all those I know.

Bullet Jockey sent some info from England today. The results suggest he really does ride those bullets all the way to the X ring.
He is doing extremely well individually but is most proud of the USA team win today.



From left to right: Norm, Doug, Eric, David and Tod.

Here is a link to the event if you would like to check all the scores.

https://gbfclass.com/euros23/

Very interesting info here. Stimulated the imagination for application of this wildcat.

https://precisionrifleblog.com/2023/08/18/austin-orgain-top-shooter-spotlight-experiment-with-25-calibers/

Had a great day on the 600 YD range yesterday. Wind was mild and steady, temps were stable, and my ShotMarker and LabRadar were behaving well. 😊

We have discussed recent issues with the Alpha brass 6BRAI when compared to the Lapua offering. Over pressure with hard bolt lift is an absolute killer in BR shooting and unfortunately the Alpha BRAI brass has become a culprit. The exact cause for this is not totally clear but there are solutions.

I wanted to look at target variations and pressure differences between my Alpha and Lapua samples. So I put together two ladders using the brass as the only variable in the reloading components.  Every other component other than brass was sorted to be as most consistent as possible. The same dies and reloading protocols were used for each ladder. The Alpha ladder was started after 10 fouling rounds were down the barrel. At this point I wish I had recleaned the barrel and put another 10 fouler rounds on before starting the Lapua ladder. I didn't - the Lapua ladder immediately followed the Alpha ladder but after the barrel had completely cooled.

The node for my 6BRAI came in at around 2940 fps for the Alpha brass, and around 2980 for the Lapua brass. Same day, same conditions, same shooter, same rifle, same reloads except for the brass.  The Alpha brass did not try to node up around the Lapua 2980 range and the Lapua brass did not try to node up at the Alpha 2940 range.

Why the difference I wonder?
Possibilities:
Different amount of fouling on the barrel?
Different case brass hardness? (Alpha is hard-hard)
Different case capacity?

I don't know the answer but would prioritize the case capacity. For velocity of the Lapua brass to reach that of the Alpha, required an additional 0.2gr of powder on average. I suppose that increased powder requirement could be do to increased friction from additional fouling or to brass hardness resulting in less case volume expansion. The later possibility however, still points to case capacity. I am trying to think through case capacity variance as it relates to pressure curve changes and the relationship between pressure curve shape and size as it relates to barrel harmonics.

Like I said earlier - I don't know the answer but found it interesting and decided to share. What are your thoughts?

Last two matches at CRC I have DQed in Heavy Gun. It was nice to get the monkey off my back today. Got caught with a couple wind let offs but was able to catch them before disaster struck.

Happy Independence Day everyone! We are very fortunate to be able to fight for the freedoms God has bestowed upon us. The last decade seems to have been very difficult in this respect, but I believe it takes occasional turmoil to temper our resolve. Today is the day I look towards our constitution and feel blest our nation's forefathers had such phenomenal insight and perseverance.

Works better than I expected and is a real improvement over what RCBS offers. Available on eBay.

It's specifically designed for the Rock Chucker and similar presses.

Interesting article on improving Savage hard bolt lift from Grimstod on AS.


https://deshind.com/2022/10/15/another-way-to-make-savage-bolt-lift-easier/

The wind at CRC didn't get above 10 mph on Saturday - that's just about unheard of! 

BUT: it ranged from 3-10 mph straight into the benches with totally random switches from the left and then the right at around a 30% value either way 😂. For me that has to be one of the worst conditions, resulting in both vertical and horizontal dispersion. All of our groups attest to the challenge. It was a very fun day though and we are all anxious to get back to fight that fickle 1000 yd course.

A friend of mine who is new to benchrest shooting and reloading just purchased a BR long range rifle chambered in 6x47. He has asked me for reloading advice on this cartridge. Unfortunately I have no prior experience there. The limited reading I've done says the case will push even the higher weight 6mm bullets into the 3100 to 3200 fps range, however, there still seems to be a precision problem with those bullets above 110 gr in weight. Powders seem to center around the H4350 and H4831SC burn rate.
I'm curious if any of our members have first hand experience with this cartridge and would be able to share their insights.

https://youtu.be/MqIxfQ6mQyw

Good info here for those interested in tuner results.

https://bisonballistics.com/

Has any one worked with these yet?

Florida is going to conceal carry WITHOUT permit!

Seems like reloading components are gradually becoming more available. Our local Scheels store had a "no limit" on components yesterday and they had a fairly healthy inventory - albeit much more expensive than when this last shortage started. If I had wanted I could have gotten 10 bricks of BR4s. At $130 per brick I decided three were enough. 😊
If availability continues to improve we may see prices come down some but I think inflation will prevent them from returning to the "good-ole-days". I hate the increased costs but it's a relief to know I don't have to stop reloading.

After the lengthy discussion regarding bullet sorting in the thread on the Accuracy One bullet OAL sorter, I generated a question that my OCD brain had to answer.  When sorting by BTO or OAL we might unknowingly be sorting for bullet weight. So the question: Does bullet weight correlate with either the BTO measurement or the OAL measurement?

I chose to use a recent batch of Vapor Trail hand pulled 103 grain bullets because they were convenient and because this particular Vapor Trail bullet has sorted more consistently for me than any other bullet type I've analyzed. I used a FX120i scale with a 0.02 +/- grain precision. Both BTO and OAL measurements were made with a Holland bullet comparator which gives highly repeatable results.

Bullets were separated into three BTO groups of 0.569. 0.570, and 0.571 inches. Within each BTO group, bullets were separated into +/- 0.0005" OALs of 1.219", 1.221", 1.223", and 1.225".   Five randomly chosen bullets were placed into their appropriate groups to provide analysis of a total of sixty bullets.

Results: The extreme spread for weights on bullets included in the analysis was a span of only 0.08 grains (102.98 to 103.06). That range is equivalent to 5 mg or 0.0001 oz . There was no statically significant correlation between bullet weight and either BTO or overall bullet length, within or between groups.
 
Take a ways:
1). Bullet weight of this lot of Vapor Trail bullets was amazingly consistent. The company that produces this bullet employs people who are very conscientious, they purchase the very best jackets available, but most importantly they produce their own cores to some very stringent tolerances.
2). If there is a "precision on target" benefit from sorting by either OAL and/or BTO, it is not likely to be associated with consistent weight within selected lots of bullets.
3). Stated differently: if bullets in this analysis had been sorted by weight, the range of OAL and BTO measurements within the weight groups would have been highly variable.
4). The very close tolerance in bullet weight and the poor correlation of that weight with dimensional bullet measurements may be a function of the quality of manufacture of this particular lot of bullets and findings with other bullet lots or other manufacture's bullets may not agree with the results of the analysis reported here.
5). Results of this analysis do not indicated that sorting by OAL and/or BTO should provide better precision than a sort by weight alone.

The rumor mill says Plano has stopped producing the Airglide gun case. Anyone know why or if they will start making them again?

I'm wishing I had a few of them.

Happy Thanksgiving ya'll!!!!

Some of you may remember a character we all enjoyed in the past by the name of Swampthang. Swampy was outspoken and sometimes his comments rubbed the wrong way a little, but his heart was always in the right place. Unfortunately Tony has had a bad stroke and is in intensive care at his local hospital. He and the family could use your best wishes right about now. He definitely has all of mine.

Happy birthday today to the Marine Corps and a happy and proud Veterans Day to all the services tomorrow. Your sacrifices have not gone unnoticed and our respect for you is deep.