Home Forums Hunting & Shooting Hunting Rifles Kimber 84L Recoil Talk & Now Velocities

Ok, I've had a few PM's about perceived recoil in the 270Win. 84L Select. I thought about it while at the range and thought the .308 84M Montana with a 150 felt like a 84L Select with a 130 and 150 grain bullet. I've put thoughts to the free recoil calculator. I used nominal velocities with their bullet weights.
Because a wide variety of scopes have their effect on the equation, I calculated these using the factory weight of the rifle listed - no scope,rings or bases - just the rifle. Apples to apples, as they say. The numbers will be a little higher than "normal".

Kimber 84M Montana .308 - with 150g = 23.7, with 165g =25.5
Kimber 84L Select .270 - with 130g = 20.5, with 150g =21.5
Kimber 84L Montana .270 - with 130g = 22.0,with 150=23.5
Kimber 84L Montana 30-06 - with 180g = 29.5
Kimber 8400 Montana 300WSM - 180g = 33.0

So I believe you should have a relative comparison on recoil that gives you a pretty good idea what to expect.

That's a pretty hefty jump(25%) from a 270 in either bullet weight and a 180g in a 30-06.

I've been shooting a weatherby ultralight 30/06 with 180's and the 84L classic 270 with 130's during the same range session. Quite a bit more recoil with the 06 than the 270. Neither are uncomfortable to me. I think the classic is really not bad at all.

The 84L I shot seemed to recoil hardly at all.It felt just like other 270's I shoot.User friendly...

Good stuff there BW.

What weight did you assign to each Montana?

I'm thinking in the 84L MT will be around 6 oz's heavier than the 84M.

12 oz's added for each rifles optics and mounts?

Brad, I assigned 5.25# as the weight for the 84M and 5.75# for the 84L. These weights then separate the two rifles by 8 oz..
That jives with the catalog data with the 84M (.308)being 5#2oz and the 84L being 5#10oz..

Again I did it this way so as to not have the rings, bases and scope skew the data higher or lower.

As you can see, there is quite an increase in free recoil with the 84L Montana using the 180g in the 30-06.

Thanks Joe, I was wondering. I used an online calculator and came up with slightly different figures, but I assigned them each 12oz's for scope and bases.

Brad, I don't think the slightly different result is that important as long as the empirical data shows that heavy rifles mitigate recoil and so on.

As to your 12oz., that is ok. I figured my total weight this way - 13oz. oz for the VXIII 3.5-10x40, 4 oz. for the Talley LW's and 2 oz for the Butler Creeks flip ups. that is 19 oz.
I could re-do the data, the numbers will be lower but most importantly relative to known recoil effects.

The other aspect is what you used for velocities.
For the 130g in the.270 I used 3050fps, 150g. 2850fps
For the 150gr in the .305 I used 2900fps
For the 180gr in the 30-06 I used 2800fps
For the 180gr in the 300WSM I used 2950fps

Ok, now running the data again with a rifle heavier by 16 ounces I come up with the following results. I excluded the 84L Select as we are talking about about kevlar stocks now.

Kimber 84M .308 with 150gr = 19.75ft/lbs
Kimber 84L .270Win with 130gr = 19.0
Kimber 84L .270Win with 150gr = 20.0
Kimber 84L 30-06 with 180gr = 25.0
Kimber 8400 Montana 300WSM with 180gr = 28.5

BW, The Talley Lwt's are 2oz's. I used a Leupold 6x36 which is 9.5 ounces... and since I can't stand Butler Creek caps, call it 12 oz's

But your point is well made...

Ok on the Talleys, but as long as the "all up" weights are the same, the formula will treat it proportional.

Weighing a sets of Talley LW, low, extended front yield 950 grains. With 7000 grains to one pound we have the Talleys weighing 2.17 ounces.

Butler Creek flip ups weigh 210gr to fit my scope. That is .5 ounce.

So using 16 ounces in the second set of data is accurate for using a 13 oz VXIII scope. So again, our actual numbers will be slightly different but the conclusion the same.

After all this, you could conclude that the .308 Montana and the .270 Montana will feel the same based on their numbers.
The 30-06 Montana with a 180gr represents a significant increase in felt recoil. Of course the 300WSM beats all and we all would know that without running the numbers.

How will different bullet weights look using the 84L Montana 30-06?

Ok here is the data with the 30-06 84L Montana with a weight of 6.75#. The velocities are nominal based on a review of Nosler #6.

150gr. @ 2950fps = 21.9 ft/lbs
165gr. @ 2875fps = 23.7
180gr. @ 2800fps = 25.1
200gr. @ 2650fos = 26.4

The equation yields a perfect relationship with what you would expect.

Here's the recoil calculator I like and gives a nod to our Mule Deer:

http://kwk.us/recoil.html

This one is more conventional and will yield a different result:

http://www.handloads.com/calc/recoil.asp

Yep, I use the bottom version.
Now to some velocity data. I did this out back as the snow condition at the range isn't yet conducive to setup - maybe in April? Anyway, I ran 3 shot strings of 3 different loads just to get SOME data. The averages are:

59gr. H4831SC, 130 Partition, Fed 210 @ 3.300" = 3009fps

57gr. H4831SC, 140 Accubond, Fed 210 @ 3.345" = 2848fps

55gr. H4831SC, 150 Partition, Fed 210@ 3.300" = 2722fps

Just to point out a factor of Nosler Seconds that is important.
The "seconds" that are sold in Partitions can come in two ways. If it has a cannelure, it is a retail factory over run and most likely a premium. It if DOES NOT has a cannelure it is a blemished second that is not suitable for the "black box".
These two are very different in length and what measurement you get using the Stoney Point tool to see where they touch the lands and groove.
For example, the 130gr. Parition non-cannelure touches my 84L at 3.300" where the cannelure touches at 3.300". That is important when seating up a starting point of lets say .030" off the rifling.
Another example is the 150gr. Partition. The non-cannelure touches at 3.335" and the cannelure style touches at 3.260".
That is a huge difference of .075"!!! I measured and re-measured this two over a year ago when they didn't look like they had the same profile. Just so you know.....

Another typical scenario showed up again. The 140 gr. Accubond is the longest bullet I use - at this time.
In my 84L is touches the rifling at 3.405" Fine. And I have never scene one with a cannelure by the way. The maximum magazine length is 3.365" BUT the angle of entry into the magazine with the ejection port is shorter yet. Nothing more than 3.345" will slip easily past the ejection port angle. So that means my 140gr Accubond is starting at .060" off the rifling. Not to worry as we have scene this crop up in Tikkas and A7's with their one magazine length fits all approach.
Accuracy? Won't know until I get back to the range.

Just some of the quirks to hand loading.

Joe, you likely know this, but your loads are quite conservative.

Most 270 will handle 58.0 H4831sc with a 150 no problem.

Thanks for the magazine/throat info.

Yep I know. I just wanted to start very conservative and see what the 24" barrel will do. As more here test their own 84L's behind a chrony I would expect data to creep up close to a 270WSM.

Yep, I hit 3274 with a 130 Nosler solid base in mine with RL-19. Needless to say I backed off. There were no traditional pressure signs other than the chronagraph.

Bigwhoop,

Could you run the numbers with a Montana 7WSM? 140 and 160 grain bullets?
Thanks!

That's with talley LW's and VXIII 2.5-8 if you want to be that exact...

Jeez Ray, be careful out there! Wow!

Ok Marty, the Montana is 6# 3oz., the scope you listed is 11.5 oz plus 2.0 oz for Talleys - let's call it 7# even.
Sort of picking thru Nosler #6 for speeds, I came up with this:

Kimber 7WSM Montana, 140gr. bullet @ 3175 = 22.2 ft/lbs
Kimber 7WSM Montana, 160gr. bullet @ 2950 = 23.5 ft/lbs

Let me know if the velocities are close to what you are seeing.