Rifle Barrel Dynamics
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- Опубликовано: 28 авг 2024
- First published 11-11-2020 on our Patreon channel, we now share it here.
Randy discusses the importance of lands and grooves, rifling forms, twist rates, dimensional aspects of rifle barrels. Should you expect a match rifle to not copper foul? What to expect with load work-ups.
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I can't get enough of this type of information. Thank you!!!
Man, I love your videos. It is always the "real deal" without any of the questionable BS one sees on a lot of gun channels.
Dont watch ron spomer
Thanks for making these NO B.S. videos. -- your the teacher of educated men..
Great info on barrels from the man that knows🙌
Here's my experiences:
Shilen -
300RUM, 7RemMag, 280 Rem (2). First barrel brand that produced caliber sized 3 shot groups (the 7RemMag), 150 Nosler Btips, IMR4831, Win brass, 215m primers. All top tier
Hart -
30-06, very rough start, first 25-30 or so shots reminded me of a poorly manufactured production rifle despite the trued 700 action, Jewel trigger, McMillan stock. Improved dramatically with more rounds. At about 50, the barrel went from a dud to a stud. Had me worried in the beginning. Identical experience with my 7PRC. My first Hart was a 270 Win on a Ruger M77 MK II. Stark contrast. This one was magic from the first shot. All turned out to be top tier
Broughton -
One of my best firearm experiences here as well. 270 Win. My first rifle to repeat half inch at 200 yards with 3 shot groups - 150 Berger VLDs, IMR4350, Fed match magnum primer, Win brass (sub zero wolf hunting load). I can't think of any handload or factory ammo I've shot in this rifle where it printed over 5/8" at 100. Built by Greg Richards, who purchased Broughton barrels from Harold Broughton
PacNor - 30-06, 270 Win, really good
Lilja - 270s, 30-06. Second brand to produce caliber size holes with 3 shot groups at 100 with handloads, again Nosler ballistic tips
Obermeyer - 1 barrel, 308 Win, 5R, D3 contour, Sako M591 - really good
Krieger 4 grooves - 270 Win, 7RemMag. Immediate top tier as well. 150 Berger VLD, H4831SC, 3000fps, quarter minute in 270. 168 Berger, Retumbo, 3000fps, first to produce caliber size 5 shot groups to quarter min
Bartlein -
6.5-284 Norma 5R gain twist. I could survive parting with every rifle with every barrel and just keep this for everything. Has never printed any bullet, handload, even while finding OCW, seating depth, bullet, primer changes, etc. over 1/2". I've never experienced anything like this, ever. Current load is 127 Barnes LRX over H1000 at 3250fps. Prevous load is 130 Nosler AB over Re19. Next is a very new 280AI. Top Tier, 168 Berger VLDs over H4831SC at 2980fps - quarter min, and 139 Barnes LRX over Superformance at 3300fps, 1/2"
Brux -
6.5-284 Norma, 140 Berger VLD, Retumbo, quarter min over and over, 4 groove
7PRC, 180 Berger VLD, LRT, ADG brass, 215match primer, 77.8 grains of powder, 1 hole, 4 groove
280AI, haven't even tested ammo yet but it's shooting Norma factory 280 Rem tipstrike into half to 5/8" so I just used that and tagged 3 deer with it this past November. No clue what it will do once I start handloading.
300WSM modified - 4 groove, 210 Berger VLD, 2880fps, Reloder 22, ADG brass, 215 match primer, still testing as well as with 190 ABLR and 190 Speer Impact. I could part with all rifles and keep any of these. All 4 groove
Benchmark -
two near twin 308 Win, McMillan stocks, TT Diamonds, Defiance actions. These are "5R" style, cut-rifled. Only had time to run 40 rounds through each with factory Fed gold medal match 168 Sierras which did really well - up to 1" with 10 shot groups but both shoot the 130 TTSX over TAC into 1/2". Still testing but clearly keepers
one 7PRC on a Lone Peak Arms Razor Ti, AGComposite stock, TT Diamond. Have yet to handload for it but it eats factory Federal ELDX repeatedly, to my satisfaction. Filled 3 tags last November with it
K&P -
these are new to me. Cut-rifled, steel comes from Germany. All of mine are 4 groove. Only one I have complete at the moment is my new 270-7PRC, 8 twist, #4 contour (I have 2 of these). Winner so far. 7PRC ADG brass necked down to 277. 170 Berger VLD at 3266fps. Using Berger's website, this outperforms the 7PRC with a 180 Berger VLD at 3000fps and the 195 EOL at 2900fps in drop, drift, energy. This, and the Brux 300WSM modified are used on my Terminus Zeus QC long action. For the 270-7PRC I will also be testing the 170 ballistic tip, the 165ABLR, and likely the 155 Barnes LRX
Got 2 barrels on order from Benchmark in .277, an 8.5 twist and a 9 twist for more 270-7PRCs but these are button rifled, Also have 2 Brux, same 2 twist rates, also for 270-7PRC. Got a 9.5 twist Brux on hand and I'm considering putting it with a Tikka action for a 270-7PRC and use the 150 Nosler ABLR
In my limited experience, the cut-rifled barrels collectively were by far the easiest and fastest for me to find loads. For whatever reason, those 2 Hart barrels mentioned above had me quite frustrated in the beginning even though all turned out to give me the WOW factor. I fully expected the 7PRC and 30-06 to be a breeze like my 270. I don't understand the metallurgy and don't plan on learning it and also don't understand why some barrels, despite quality and reputation take a lot of firings before they reveal how special they really are while others shout at me from the get go, "hey bud, your search is over."
Based only on my experience, if I had to choose only 1 button brand, it would be Broughton hands down and of course, you can't get those anymore and I only have the 1. In fairness, I haven't shot a Benchmark button rifled barrel yet
Boots Obermeyer is a mentor and I have known him for a number of years.
He is up in years and had a stroke a few years back and no longer making barrels.
Boot’s had 5R and 6R barrels.
The “R” is for Russian, not radius, this stems from the land and groove design the Russians used in their 25mm and larger barrels. Boots did extensive testing for the US Government in 60’s on Russian barrels, he found that bore and groove had a radius, no square edges and corners. The reason for the design the powder the Russians were producing was extremely dirty and each round fired would sweep the bore and low copper buildup. All he did was incorporate that design into rifle barrels.
I could go on into further findings that were observed by doing this. Also Boots had .002” tight bores ie. .298”-.308”: .010” difference between bore and groove instead of .008”.
Great information. I have to explain this to people regularly.
So much enjoy the voice of experience!! thanks
I chose PacNor because they’re in my state of Oregon, Brookings on the South coast for my go-to ‘82 M-77 Tang Safety Ruger for Blacktails. I purchased a 1 in 8-1/2” twist, polygonal rifled, chrome moly, 260AI chambered, 26” Sendero contoured barrel. It’s a tack driver and I’m happy with its performance @600 yards or less.
Thank you.
I enjoy listening to your wisdom.
It is reaffirming, when it matches what I know. & when it doesn’t, it causes me to examine what I thought I knew.
Another great video Randy!! Thanks so much for your wealth of knowledge. You're a real "straight shooter"!
I tried some Sierra Match kings in my bull barrel 24 inch 308 and they shot into a cloverleaf.
I then tried the 180 grain Hornady SST bullets loaded the exact same way with the same powder charge and the same overall cartridge length and it poked all three into the same damn hole with very little variation. This is the load that I am still using for the gunrange and have made everyone else green with envy because they haven't been able to beat it after many shooting matches.
It just absolutely kills them because they are using Match kings and so forth. I know that what you are saying is spot on.
You're something else Mr. Randy.
I've been a shooter and reloader for many many years, and you are 100% correct.
My friend had an old 303 British that only had 2 grooves that sit on opposite sides. I don't mind telling you that dadgum old gun was extremely accurate to 200 meters with the iron sights.
Shot an 03 Springfield with 2 groove , it seemed to shoot everything well and fairly accurate.
The 03A3 Springfield had a 2- groove barrel and shot fine. Not sure about the original model 03.
Thanks for the information and discussion. I’d like to suggest “barrel contours and considerations” for a future topic. I’m interested in your preference for barrel contours for larger magnums.
Hello Randy, thank you for all of the valuable information that you provide. Also thank you to Cathy!
Here is my question, can a barrel in a Remington model 710 in 7mm Rem Mag be replaced due to it being pressed in?
Again thank you for your time,
Todd Clark
Thanks so much also to Cathy , Randys wife. Behind every great man is a great woman. I'm sure you have contributed just as much to the success of your business as he has. God bless you both.
Aw, thanks so much, Michael! God bless you and yours. He does bless us [even when things may not go as we think they should!].
Thanks for watching, from us both!
Maybe I don't understand. I thought you only needed enough twists to stablelize the bullet. Not more or less. Maybe I am wrong.
What does "stabilize" mean to you? Most people can't answer this accurately.
Best barrel made is HART in my opinion also, great company to deal with, im waiting on my .284 barrel in rem adl contour 1and 8 twist for a 7 prc build.
They are fantastic people, putting out a fantastic product. Wonderful people and top in customer service.
Thanks for watching.
so considering all of this - and all respect to you and all other past barrel makers current , past and future - but in your opinion was there anything special about the quality of Pope barrels rifling compared to modern rifling?- was it the man himself with a special ‘supernatural’ touch to barrel making or was he just more accurate compared to most of his day so he stood out?
Nothing special.
Thanks for watching.
👍🏻👍🏻
I might be mistaken but the way I see copper fouling is that the deposit left after a copper bullet passes down a rifled barrel should decrease the amount of imperfections in the bore. Basically filling the voids to create a smoother bore.
Shouldn't that be mostly desirable?
There is no void in an on dimension match quality barrel. Tight or loose spots are a problem in cheap production and that is never an asset. Why bother, when there are so many great choices. Copper fouling is not something to be desired or wanted in a good match quality barrel.
Thanks for watching.
I've always heard great things about Hart barrels, but I've never used one.
They are the best, hands down. I've used many others, and find that none can compare in quality. Douglas Premium air gauge barrels, for blued chrome-moly come in close second. I've found too many variations in even the other "top" barrels.
Thanks for watching.
Doesn't Bartlein mark their barrels with the dimensions?
Yes, they do. I don't find their tolerances up to the standard of Hart and Douglas, however.
Thanks for watching.
Terrific info-video.
Help me here Randy, you say it is ok (time 7:01) to have a bore/groove variation of 1 or 2 10/1000 of an inch. Then you bust on Krieger because their barrels are off by 1/1000 of an inch, curious which is better? Best I can figure is 1or 2 ten thousands (10/1000) is pretty sloppy tolerance for a rifle barrel.
10,000 of an inch vs 1000 of an inch
.3081 vs .309
@@lisaannaallen6283 Whew that makes more sense. With CC on it says "ten thousands" when it should read "ten thousandth".
.oo3
Learn how to read a micrometer and speak measurements please. .002 o
If you have a match grade barrel or top quality barrel; it will shoot. I’ve had 4groove, 6 groove and they all shot. No difference. I had an old .303 left twist 2 groove and it shot very well. I have a custom.243 gain twist and it is a one holer. Just remember to torque action and scope rings and bases properly.
Hey Randy , I have read all my life about inherently accurate cartridges ( in magazines from gun writers ) . Doesn’t the chamber and barrel control the accuracy of the rifle ? In my mind the cartridge just holds the primer , powder , and bullet and has little to do with accuracy itself . I feel ( any ) cartridge can be accurate with a Good barrel ! Your expert knowledge and opinion on this please would be greatly appreciated . Thanks for all your hard work for us !…….
The cartridge has everything to do with accuracy, everything else being correct.
Try reloading various different combinations of primer, powder, bullet, and see how much difference in accuracy, or lack thereof, you can get.
There would be no point in working up loads if primer, powder, bullets, and cartridge [size, etc] had little to do with accuracy.
Thanks for watching.
I was planning to send Hart an action for rebarreling. Still am, but might have to wait longer for return with your advertisement, betting businesss picks up.😏
They are busy people because they are good people putting out a top quality product.
Thanks for watching.
I could care less about having how many groves my barrel has stamped on it i would rather have the chamber/neck size stamped on my barrel vs how many groves it has..
The chamber, by law, and common sense, is stamped on the barrel. A barrel blank should have, when ordered, the groove stamped on the end of the barrel, which will be machined off anyway, in the process of threading.
Thanks for watching.
I went with Douglas Premium, and have no complaints. Cold bore bullseyes are boringly repeatable.