30-06 recoil, Hornady Interlock vs. Barnes TTSX

[MWC1974]

Dialed in a few loads over the last few weeks. Both very accurate and group very well out of my Savage model 111 30-06. One of which has a very noticeable recoil over the other, any reasons why?

150 grain Hornady interlock with 58 grains of IMR 4451. Sub MOA, standard recoil and no pressure signs.

165 grain Barnes TTSX with 54.5 grains of IMR 4451. Sub MOA, recoil was almost punishing and no pressure signs.

Both shot out of a lead sled and performed very well. The Hornady was seated to manual specs. The Barnes was seated to .05 off my rifles lans. So my question is, what causes the increased felt recoil between the two?

 

[ms6852]

Newton’s Third Law states that; for every action, there is an equal and opposite reaction. So, in terms of shooting it means that the powder explosion produces hot gases that expand pushing the bullet and gas down the barrel (action) and so the equal and opposite reaction to this is recoil.

The heavier bullet has a direct impact on recoil over the lighter. The 30-06 is my favorite hunting caliber and I stopped using 180 grains bullets for elk. My rifle loves the 165 grainers and am happy as it shoots them sub moa at 200 yards, which is great for deer and elk.

 

[MWC1974]

Thank you. I’ve shot many many boxes of Remington Cor-Lokt 180grs out of this gun. I don’t recall the recoil being like it was with the 165gn TTSXs. Maybe my memory is poor, or maybe I’ve become accustomed to the 150s?

 

[MWC1974]

My wife and I have hunted with 7mm cartridges for over a dozen years (7-08, 7-08AI, 284 win, and 7mm wsm) here in mid-MO. We see some decent size bucks and have taken a few in the 215-225# range.

We've have used 120 TTSX, 140 TTSX, 120 NBT, and 140 NAB. We have never had a DRT with the TTSX, but all have been one shot kills with generally fairly short runs after the hit.

The 120 gr NBT and the 140 gr NAB have both given excellent results IMO - several DRT shots and short runs if not.

While the TTSX is a very fine bullet, for deer, I like the BT or AB.

Thanks. Any difference in felt recoil between the two?

 

[jmr40]

Note: The 1st paragraph was written after the rest, but I felt it important enough to add it at the top

Here is my guess. Both of those loads are slightly over max according to my sources. I'm GUESSING that the 150 gr load is still OK, but you may have an overpressure problem with the 165 gr bullet even though you're not getting pressure signs. This is where a chronograph comes in handy. According to my book load data you should be at about 2800 fps with the 165 gr bullet. But if you're over pressure it could actually significantly faster, which would mean more recoil.

Recoil is a factor of 4 things

Weight of the projectile
Weight of the powder charge
Weight of the rifle
Muzzle velocity

There are several online sources where you can plug in the numbers. Here is one.

JBM - Calculations - Recoil (jbmballistics.com)

In this case the difference may be between your ears. Looking up load data you should be getting right at 3000 fps from the 150 gr bullet. From an 8 lb rifle that translates to 20.7 ft lbs recoil with recoil velocity at 12.9 fps

The 165 gr bullet should be getting around 2800 fps and from the same 8 lb rifle you'd be getting about 20.4 ft lbs recoil with recoil velocity at 12.8 fps

The actual velocity you get may not be exactly what I estimated, but either way the recoil should to be VERY close to the same between those loads.

FELT recoil can vary depending on other factors. Stock shape and weight matters. Some guns just kick harder for some people if they don't fit. Recoil velocity is a factor. A 300 WM firing 180 gr bullets has almost exactly the same recoil as a 35 Whelen firing 225 gr bullets. But the 300 comes back at the shooter FASTER, resulting in more discomfort even though the actual recoil is the same.

But since you were firing these through the same rifle stock shape isn't a factor

 

[MWC1974]

Note: The 1st paragraph was written after the rest, but I felt it important enough to add it at the top

Here is my guess. Both of those loads are slightly over max according to my sources. I'm GUESSING that the 150 gr load is still OK, but you may have an overpressure problem with the 165 gr bullet even though you're not getting pressure signs. This is where a chronograph comes in handy. According to my book load data you should be at about 2800 fps with the 165 gr bullet. But if you're over pressure it could actually significantly faster, which would mean more recoil.

Recoil is a factor of 4 things

Weight of the projectile
Weight of the powder charge
Weight of the rifle
Muzzle velocity

There are several online sources where you can plug in the numbers. Here is one.

JBM - Calculations - Recoil (jbmballistics.com)

In this case the difference may be between your ears. Looking up load data you should be getting right at 3000 fps from the 150 gr bullet. From an 8 lb rifle that translates to 20.7 ft lbs recoil with recoil velocity at 12.9 fps

The 165 gr bullet should be getting around 2800 fps and from the same 8 lb rifle you'd be getting about 20.4 ft lbs recoil with recoil velocity at 12.8 fps

The actual velocity you get may not be exactly what I estimated, but either way the recoil should to be VERY close to the same between those loads.

FELT recoil can vary depending on other factors. Stock shape and weight matters. Some guns just kick harder for some people if they don't fit. Recoil velocity is a factor. A 300 WM firing 180 gr bullets has almost exactly the same recoil as a 35 Whelen firing 225 gr bullets. But the 300 comes back at the shooter FASTER, resulting in more discomfort even though the actual recoil is the same.

But since you were firing these through the same rifle stock shape isn't a factor

Thank you. The 150s are sitting at 2800 and the 165s are sitting just under 2975. According to published load data and GRT, I have ~ 2 grains of wiggle room for both loads. Well… GRT thinks is I only have ~1.5 grains left of wiggle room on the 165s. I’ll load up a few more 165s with 53.7 and 54.0, cronograph both and see if it makes a difference. I will say, the node was right at 54.0 when I did a ladder test with the 165s.

 

[Riomouse911]

Hmmm… the load is charged with 3.6 grains more of the same powder, 15 grains less bullet weight… and its 175 fps slower?

Man there must be a ton more friction in the 150 gr load compared to the mono metal one.

As for the the increased recoil, your numbers show you why: using the same gun you’re shooting a heavier bullet that’s going at a 175 fps faster speed. Ol’ Mr. Newton wins again…

Stay safe..

 

[MWC1974]

Hmmm… the load is charged with 3.6 grains more of the same powder, 15 grains less bullet weight… and its 175 fps slower?

Man there must be a ton more friction in the 150 gr load compared to the mono metal one.

As for the the increased recoil, your numbers show you why: using the same gun you’re shooting a heavier bullet that’s going at a 175 fps faster speed. Ol’ Mr. Newton wins again…

Stay safe..

Thank you. I’m starting to get a better understanding of the felt recoil, which.. I should have known. But now you’ve got me thinking, what would cause the increased friction? I think I’m going to cronograph both again the next time I head to the range. I didn’t cronograph them yesterday as my only purpose was to zero my rifle for the upcoming deer season. The 150s are dead on at 100 yards and the 165s are an inch and a half low at the same distance. I get the heavy bullet drops more than the lighter one and I’m not worried about that. Just curious about the recoil, but now a little curious why the difference in speed that you bring to light (which I did not think about).

The 150s are 3.21 COAL (Hornady recommended) and the 165s are 3.281 (.05 off the lands as recommended by Barnes).

Thanks again fellas, keep up the great advise and feeback.

 

[Aletheia]

I think I’m going to cronograph both again the next time I head to the range. I didn’t cronograph them yesterday as my only purpose was to zero my rifle for the upcoming deer season. The 150s are dead on at 100 yards and the 165s are an inch and a half low at the same distance. I get the heavy bullet drops more than the lighter one and I’m not worried about that.
.

I think you should chronograph them again to check numbers. There is no way that a heavy, faster bullet drops more than a lighter, slower one due simply to the weight of the bullet. Different points of impact are due to many factors, but bullet weight cannot be used to predict anything other than it will likely be a different POI than another bullet. But ALL different bullets will likely be different in POI even with identical powder charges. Any change in components will most likely produce changes in POI. If you are using a lead sled (which I wouldn't ever do) how do you measure differences in recoil?

Your reported results do not make a lot of "sense" to me. I would be trying to isolate variables and test until I found out why things are happening as you describe. Recoil is the result of the speed and the mass of stuff that goes out the end of the barrel. Pure physics. The numbers you are reporting do not match what I would expect. From your description, I cannot give you any advice about "why", but I would try to find out, because any anomalies in reloading results can indicate something is not right. I think reloading is an activity that makes me very cautious when I encounter something that doesn't fit what the laws of physics say should be happening.