Barrel Twist Rate and Length Question

I have now watched Snipper101 through episode 69. Episodes 68 and 69 answered a number of my questions. I went back to my table of possible bullets and found Hornady ELD-X or ELD Match 162 gr PTBT bullets, G1 BC of 0.610 and 0.670 respectively, would be worth a try in a stock Remington 700. Does anyone agree or disagree with this?

Check out http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi JBM has multiple FREE calculators, which can give you an idea of what kind of performance you can expect depending on all your variables. My 500m range has been closed for nearly a year, but to 300 meters the JBM calculator seem accurate.

My rifle is a semi-auto. so I can't help with rifle choice. Looking to get a bolt gun eventually, but will wait to see the reviews on the new Howa, Bergara, and a couple of other new offerings.

Geoff, Thanks for pointing this out. I knew there were some good tools on the JBM website, but I had only used the trajectory calculator as Rex explained how to use it a couple of episodes back. The stability calculator was very helpful in terms of answering my original questions, as well as visualizing how each of the bullet parameters act on stability. Thanks again.

My pleasure!

also have a look at Howa don't under estimate then 800 dollar and spend 200 tuning and it will be a good stater then later put a good barrel on it and tweak the trigger

Look at I think the last uploaded video. Rex gives some very good pointers on long range on a budget.

Don't forget that if you're on a budget you don't HAVE to start with a new rifle. If you've got something that'll shoot sub-moa that you can afford to feed, and you can afford to get a reasonably good scope for it, get a chrony and something to measure temp/pressure/wind-speed with and a compass and you're good to at least start learning. :-)

Having said that, yeah, the twist rate definitely matters. I had one heck of a time trying to get an old .270 to shoot big, heavy slugs with a high BC until I realized (face-palm) that the twist rate wasn't anywhere near fast enough. So, shooting lighter slugs my max range on this old off-the-shelf rifle limits me to around 1100m at my altitude but that's good enough for me to start learning. The lighter rounds mean I really gotta get my wind call right also but that's ok - I'm not shooting in any competitions or anything, just shooting for fun and to learn.

Since you mentioned 7mm-08 I assume you're reloading too? Or that you already confirmed you can get off-the-shelf ammo that's match-grade? If you're reloading, you may want to play around with bullet seating depth too. On that old .270, especially with the lighter slugs, that seems to make a big difference in getting it to finally shooting sub-MOA.

Lesssparks, A couple of questions…… 1. What is the primary purpose of your rifle going to be? 2. Do you reload? 3. What is your budget for an optic? 4. Have you looked into other cartridges like 6XC, or 6.5 Creedmoor?

I ask this because all these calibers have light recoil, but how availible is the ammo in your area? If you reload this might not be as big of a consideration. Also 7mm-08 is extremely hard to find in the proper rifle configuartion without having to do a ton of modifications, that most long range shooters are looking for in a long range system... Please allow me to explain. In most long range set-ups you will commonly find a heavier barrel, with an adjustible stock (adjustable cheek riser, and length of pull) and a very crisp trigger. and if you wanna squeek out the extra velocity, it helps to have a longer barrel length. I just looked at Gun Broker and found there are alot of options with most of those charactoristicsand within your price range in 6.5 Creedmoor. With minimal gunsmithing work or materials (depending on how compentent/confident you are with basic gunsmithing) most of those rifles are already running a stiffer chasis/stock and the longer heavier barrels 24” most long range shooters prefer vs. 22” in the 7mm-08. Things you might consider doing to any rifle is at least skim bedding the recoil lug and possible replace the factory trigger with a quality Jewell, Timney , or Huber.

The 6.5 Creedmoor is similar ballistically to the 7mm-08 with slightly less recoil. There is a plethra of 7mm-08 ammunition where as 6.5 is a little more challenging to find at a Big R or ACE Hardware store. If I was in your shoes I'd seriously look into a 6.5 Creedmoor. Some other very good long range rounds I didnt mention becuse they are not as plentiful in ammunition selection and availibility would be 6x47 Lapua, or 6.5x47 Lapua. I doubt you would be unhappy with anyof these. I would highly suggest you invest in a quality optic, you can skimp of the rifle, but would tell you to purchase as much optice as you can afford. Hope this help you out!

As far as twist rates you can find twist rate calculators, to determine what you might prefer according to bullet wt/gr and velocity. I use Bergers website alot http://www.bergerbullets.com/twist-rate-calculator/ Cheers!

Alaskan Long Range Hunter, I have not considered 6.5 Creedmoor. I guess mostly because it was not included in Rex's early videos on cartridge selection. 6.5 Creedmoor has gained much momentum in the time since Rex made these videos.

To answer your questions:

1. The purpose of this rifle is long range (600 - 1200 yards) target shooting, but I would like to have the ability to shoot targets up to 1500 yards.

2. I plan to reload for this rifle. I have not reloaded since I was a starving graduate student some 35 years ago. I really enjoyed reloading in those days. I plan to buy all new equipment. I plan to leave some money in the budget for reloading equipment, but I was hoping to use factory ammo until I am shooting well out past 300 yards or so. I am expecting to spend $500 to $700 on reloading equipment.

3. I planned to buy the low end optic that Rex recommends in his videos - SWFA SS 10X42. These were available last week, but it seems no one has them in stock this week with a mildot-mildot reticule. There are a couple of these scopes with MOA reticules available. These scopes run $300 for rear focus and $400 for side focus. The IOR Valdada scope is the next level up the price range of the scopes Rex recommends. It is a little more money than I would like to spend at this point - $750 to $800. I have not been able to find any of these scopes either. What are your recommendations?

My thought process is to get into long range shooting as inexpensively as possible until I see that this something that I enjoy doing. I do not have a problem spending money on hobbies that I really enjoy.

I had pretty much settled on a Remington 700 SPS rifle in 7mm-08, 24 inch barrel with 1:9.25 twist. I dug through Miller's Stability Factor equation last weekend. It looks like 1:9.25 twist will stabilize rounds up to the 162 grain or 168 grain range. I realize that after a couple of years, the action may be the only part of this rifle that I am still using.

I started looking at the ballistics for 6.5 Creedmoor this morning. I like what I see, but I want to spend a little more time looking through the data before switching to that cartridge. I will start watching the GunBroker auctions to see what is available.

Thanks for the help.

Im glad you thought is was helpful....I have not personally shot a 6.5CM, but a lot of guys in the Pro Series like PRS are shooting with the calibers I told you about more specifically 6.5CM. Its a great little cartidge.