How can I have my father placed into a nursing home when he refuses to go?

I grew up with guns with my father.. if your Dad is threatening to shoot someone the FIRST thing you do is REMOVE the guns from the house. With the changes going on in his brain, He is no longer responsible & safety conscious gun owner that he once was.. It may be an idle threat and just acting out, but, any threat at this stage in his confused life is to be taken seriously. He isn't going to be using them or hunting any time soon I'm sure.
As a POA, talk to Dad about new living arrangements and then to his doctor about his acting out and maybe a temporary anti anxiety medication to use now and when moved in, until he gets used to his new surroundings.
You are the parent now, be matter-of-fact, respectful and firm. Include in your talking the support of his doctors/by name and caregiver's concern. Keep your cool and steady business tone of voice. Come with a plan and 'this is it'... stick to it. Write down the moving agenda, with brochures/picture and Make-It-Happen.
You don't have time for emotion when you're protecting your loved one. Get them placed so everyone involved can breathe again.
I think the worst part is the guilt the POA feels and tries to get input from the one who needs to be cared for.. remember: THEY ARE NOT MAKING RATIIONAL DECISIONS ANYMORE or Cannot Remember what they may have said in the past.
You know what's right and what's wrong... when you do right, there is no wrong or guilt. Hugs!

Please, if there are threats of violence, take them seriously and report to police. Don't dismiss this as overreacting - so many tragedies happen that could have been avoided with honesty as to the danger.  It is usually worse than you think!

Countrymouse gives excellent advice. Dad’s brain in broken and sadly, the dad you knew decades ago no longer exists.

Whether he has a UTI or not, even if you get that cleared up, it won’t cure the dementia. All it did for my mom was tone down her combativeness and penchant for hitting, gouging and pinching everyone.

The way you place him is to tour facilities. If he’s not already on Medicaid, file for it for him. An alternate solution is to wait until his next “meltdown”. Call 911 and have him Baker Acted to a psych ward and call your APS case manager. Tell them you cannot and will not bring him home. They will have to find a place for him.

He still be competent to know if he going to a NH probably means the end.

Your father may have a UTI, urinary tract infection. This can cause extreme behavior and can often be remedied by an antibiotic after a simple pee test.
Does your father have a gun? If so, you must have it (or bullets) removed from his access.
Start with the UTI. If you can’t get him into his doctor, try an urgent care. Tell them you would like a culture in order to get the correct antibiotic to treat the UTI. If the initial test is positive for an infection, they will generally do the culture anyway.
Sometimes a doctor will let you bring a urine sample in for testing.
People are often surprised at how radical a UTI can cause a loved one to act.
If your fathers current behavior is not typical of him I would highly suspect the UTI.
You sound like you have your hands full with trying to work and take care of grands.
In order to force your father into anything, you may have to file for guardianship.
As has been mentioned, many facilities would not want to deal with him if he is violet. They are not equipped.
if you haven’t already had him tested for a UTI, please don’t discount that as the underlying problem.
Go over his meds with his pharmacy. With so many health issues, he may have incompatible meds.
Let us know how he is doing and what works to get him settled down.

You’ve been given great advice to start the search for a facility now. My concern is that hopefully his threat to shoot a caregiver was just wild talk...there are no guns in the house, correct? If not, please remove or disable them.

Everyone is waiting for you!

You have your father's permission, through the POAs that HE gave YOU, to act. Your father's doctor and APS have both determined his legal incompetence. Your father is no longer able to make decisions for himself. His challenging behaviours make him a danger to himself and others.

These factors mean that every single box has been ticked. All that remains is for you to find a memory care unit or dementia care facility appropriate to his needs and start the admission process. You already have all of the authority that you need to take these steps.

So... have you looked at facilities near you?

He sounds beyond the need for an AL. He also sounds as though he needs medication especially since he has exhibited violent behavior. Could you get a doctor on board with that. If not a NH may refuse him. I would try to act as soon as possible with that. Then the next step may possibly prove to be slightly easier. I hope you can move forward since the present situation sounds quite bad and will not likely be remedied without further actions. If you could start with medication while pursuing the legal options things could possibly be solved to a degree sooner. I wish you the best with this difficult situation. I am dealing with a mother in AL. She is not violent but comes up with crazy ideas periodically that she repeats not remembering we have discussed them before. Some of them involve giving cousins items that I have for my children. It always creates a painful situation as I feel disloyalty towards me. It is hard to remember she is slowly losing her mind when this gets brought up again a numerous time.

There is also a less pleasant, but viable option. Check your state laws regarding mental health and when a person becomes a danger to themselves or others. In Florida it's call the Baker Act. In Georgia it's the 5150 code. Every state has one. The problem is you may or may not have any say in what the state decides to do regarding your father. I wish you the best in finding a resolution. <3

Yes, use your rights under the documents you have. You don't sound confident about that, so it might be good to go to a community legal service or a lawyer to get you up to speed. Have a look for good nursing homes in the right place (or assisted living, or memory care - whatever you think is needed), so when you are ready to act you can move smoothly to the next step. There is no point in setting yourself up for repeated dramas.