Hardness plywood vs pine

[richardtenggren]

Solid project by you, in any case, you rarely leave details to chance!
Read about the game in your renovation thread earlier

 

[AndersMalmgren]

Solid project of yours in any case, you rarely leave details to chance!
I read about the game in your renovation thread earlier

I'm taking just as long with this project as the renovation project

 

[guggen]

Pine tree, you mean a living pine? The fact is that living trees are very resilient, a fairly narrow tree can withstand even 7.62x51.

Pinewood, on the other hand, is dried and very soft, even .22 lr penetrates quite deeply. But of course, we have to modulate this correctly since pine framework is a common component in interior walls. We will also modulate drywall correctly, so it will be interesting on indoor ranges

Edit: our game is military, so it's only FMJ like the M855A1, which is the new Nato 5.56x45 cartridge

Yes, living 80-year-old trees most bullets go straight through, even hunting ammo that partially explodes inside the tree. Even a small 223 goes straight through.
Now we're talking rifle ammo and not low/weakly loaded bullet ammo.
As for generation, the diameter of the bullet hardly brings anything positive. That is, a 7.62 definitely does not penetrate better than a 6mm. For example, a 9.3*62 with enormous energy is used because you want the bullet to stop in the body, i.e., deliver all movement energy, or whatever you are shooting at. So low impact energy with a smaller, hard bullet often has better penetration. On the other hand, to get high impact energy, you want a heavy bullet and high load that still flies reasonably straight, so it's not a simple equation.

 

[AndersMalmgren]

Yes, bullets can go straight through most 80-year-old living trees, even with hunting ammo that partially explodes inside the tree. Even a small 223 can go straight through. Now we're talking about rifle ammo and not low/weak charged bullet ammo. When it comes to generation, the diameter of the bullet hardly brings anything positive. That is, a 7.62 definitely does not penetrate better than a 6mm. For example, a 9.3*62 with immense energy is used because you want the bullet to stop in the body, i.e., transfer all kinetic energy, or whatever it is you're shooting at. So low impact energy with a smaller, hard bullet often has better penetration. On the other hand, to get high impact energy, you want a heavy bullet and high load that still travels relatively straight, so it's not a simple equation.

7.62x51 is the ammo that penetrates best of the ones we have in our game, after all. We have 9x18, 5.7x28, .45 ACP, .454 Casull, 5.56x45, and 7.62x51. It's a combination of weight and speed to get the perfect bullet. As mentioned, we only have jacketed bullets in the game since it is a military simulator, but even within FMJ, there's extreme variation in their capabilities. However, we use the latest NATO standard for our rifles, which is M855A1 for 5.56 and M80A1 for 7.62, both designed to penetrate AR500 as well as possible.

Healthy trees are tough bastards, (By the way, he's shooting the predecessor to the M855A1 in the video)

Edit: we only use equations for external ballistics as this is easy to calculate with the ballistic coefficient. For terminal ballistics, we instead use graphs that we derive from data on the internet. Then a certain adjustment for whether the bullet tumbles or not.

 

[guggen]

7.62x51 is the ammo that penetrates best of the ones we have in our game anyway. We have 9x18, 5.7x28, .45 ACP, .454 Casull, 5.56x45, and 7.62x51. It's a combo of weight and speed to get the perfect bullet. As I said, we only have jacketed bullets in the game as it's a military simulator, but even within FMJ, there is extreme variation when it comes to their capabilities. We, however, use the latest NATO standard for our rifles, which is M855A1 for 5.56 and M80A1 for 7.62, both developed to penetrate AR500 as well as possible.

Healthy trees are tough bastards, (He shoots the predecessor to M855A1 in the video)

[media]
Edit: We only use the equation for external ballistics as it is easy to calculate with the ballistic coefficient. For terminal ballistics, we instead use graphs that we derive from data from the internet. Then a certain adjustment for whether the bullet tumbles or not.

None of these are really high performers. Note that the weight and cartridge size is a big reason why, both militarily and civically, they often go down in caliber.

 

[AndersMalmgren]

M80A1 is not a bad penetrator, here it penetrates double layers of cement block material

edit: Building houses removes the timestamp 4:14

 

[guggen]

M80A1 is not a bad penetrator, here it penetrates double layers of cement block material

edit: Bygga hus removes the timestamp 4:14
[media]

Yes, 7.62 × 51 mm NATO or the equivalent 308 is today one of the most common calibers and one of the smaller/weaker of the .30 calibers. But it suffices for most purposes.

 

[Telefu]

Haven't read the entire thread but can share some practical info.
5.56*54 goes right through a decimeter-thick Gotland pine at short distances and takes down shot-up Saab targets. We noticed that when we trained hunting shots in military service
Don't think plywood or homogenous wood makes much of a difference in penetration at medium-short distances. In the soldier's manuals, there are guidelines for penetration in various materials, including 70 cm in packed earth. Should be findable online.

 

[AndersMalmgren]

Haven't read the whole thread but can share some practical info. 5.56*54 goes right through decimeter-thick Gotland pine at short distances and takes down shot-up Saab targets. We noticed this when we trained hunting shots in military service I don't think plywood or solid wood makes any significant difference in penetration at mid-short distances. In the soldier books, there are rules of thumb for penetration in different materials, including 70 cm in packed earth. Should be possible to find online.

5.56x45 M855 (not A1) stops 234.95mm plywood. Furthermore, this data is the reason why I want to know plywood vs pine as I don't have good measurement data for 5.56x45 FMJ vs pine.

 

[AndersMalmgren]

I just realized I have a semi-good measurement reference. A guy shoots 9mm Federal (124gr FMJ) into solid packed plywood 100mm, and another guy also shoots the same Federal ammo but into spaced pine planks. In other words, not exactly the same thing since you can generally shoot deeper through multiple thin barriers than a solid one. But this guy shoots through 181mm of pine.

So the ratio then becomes that plywood is 1.81 times harder.

 

[guggen]

5.56x45 M855 (not A1) stops 234.95mm plywood. Otherwise, this data is the reason why I want to know plywood vs pinewood since I don't have good measurement data for 5.56x45 FMJ vs pinewood

Have you tried searching for 223 which is practically (if not completely) identical?
For example, 223 vs gel, 223 vs tree, etc
You can also google 223 vs 308 ballistics and similar.
These military calibers have civilian equivalents/identicals.

 

[AndersMalmgren]

Have you tried searching for 223 which is in principle (if not completely) identical?
For example, 223 vs gel, 223 vs tree, etc.
You can also google 223 vs 308 ballistics and similar.
These military calibers have civilian equivalents/identicals.

It's actually not exactly the same. But almost But yes. However, you don't get references for M855A1 or M855 or even the old M193 as these are military NATO FMJs and .223 is a civilian caliber. Most civilians shoot expanding ammunition as they want to kill the intruder, you know, USA. (and minimize overpenetration)

 

[guggen]

It’s actually not exactly the same. But almost But yes. But then you don't get references to M855A1 or M855 or even the old M193 as these are military NATO FMJs and .223 is a civilian caliber. Most civilians shoot expanded ammunition because you want to kill the burglar, USA you know

I know, have or have had these calibers.
They are basically the same, you can at least shoot with the same loads. However, it is recommended, though many do it, not to load military ammo in civilian weapons and vice versa.
There is a plethora of full metal jacket for these calibers as full metal jacket is used in training and also a lot of hunting.
But, for what you're trying to achieve, you should definitely look at comparisons with 308 and 223.

 

[AndersMalmgren]

I know, have or have had these calibers. They are basically the same, you can at least shoot with the same loads. However, it is recommended, although many do it, not to load military ammo in civilian weapons and vice versa. There is a plethora of full metal jacket for these calibers as full metal jacket is used in training and quite a bit of hunting. But, for what you are trying to achieve, you should definitely look at comparisons with 308 and 223.

If you search for videos with .223 or .223 Remington or .223 rem, most videos use JSP. If they use FMJ, it often says 5.56 NATO or something similar.

 

[AndersMalmgren]

Created a small devlog on this if you are interested.

Tensile strength proved useful between metals if one reference was in AR500 steel and another in softer weld steel, allowing for quite a high accuracy conversion between these. More difficult with wood though.